Micro Inserts for HPLC Vials

Item: 250ul HPLC Vial Insert
Volume: 0.25ml
Color: Transparent
OEM: Available
Sample: Free
Certification: ISO9001:2015
Place of Origin: China (Mainland)
Compatibility: 2ml HPLC Vials
Polyspring inserts are self-aligning and provide a cushion against needle contact

Conical Inserts from Aijiren are designed to assist in the consistent sampling of low-volume chromatography samples. Micro Insert is used to ensure the most accurate and reliable analysis of your lab samples. The 150 μL Conical Bottom Vial Inserts are made of clear glass and suits for 8-425 vials. Micro inserts, when used in conjunction with autosampler vials, allow for maximum sample recovery and easier sample removal because the conical shape decreases the surface area inside the vial. Analysts can use insert vials to achieve greater control over sample introduction, reduce contamination risk, improve data quality overall, ensure consistent injection volumes with increased peak shapes, optimize separation efficiency, and enhance chromatographic performance.

9mm Short Thread Vial with integrated 0.3ml Micro-Insert, 32 x 11.6mm, Amber or clear glass, 1st hydrolytic class, label and filling lines, 100/pk
Aijiren 9mm glass vial with fused insert together eliminates movement of the insert. The fused insert also eliminates concerns about contaminants around the fused seam/space between the neck of the vial and the insert. Vials without graduation, all micro inserts are clear glass. Vials with integrated Micro-Insert are also available now in clear and amber glass. amber glass makes it compatible with sun-proof samples.

Micro-vial volume is 0.3ml. this micro-vial is used for chromatography instrument. There are some expensive sample to analysis. To the needle inject the sample, so this vial is needed. Compared with micro-insert, micro-insert is more expensive. But the micro-vial is compatible with most instrument.

Micro Insert is used to ensure the most accurate and reliable analysis of your lab samples. Micro-inserts are manufactured of clear glass. Micro inserts, when used in conjunction with autosampler vials, allow for maximum sample recovery and easier sample removal because the conical shape decreases the surface area inside the vial.
Micro inserts can be used with screw tops, crimp tops, or snap-top vials. All conical styles of inserts are offered with the traditional pulled point as well as the improved mandrel point. Pulled point inserts are more economical, but mandrel point inserts provide a more pointed and uniform tip that enables better sample recovery. Micro-inserts can be used on all 1.5ml vials. Effectively relieves the pressure of the syringe. PolySpring inserts are self-aligning.

Micro inserts, when used in conjunction with autosampler vials, allow for maximum sample recovery and easier sample removal because the conical shape decreases the surface area inside the vial.

Finding suitability to be used over a wide temperature range, these 1ml Shell vials come extensively tested so as to perfectly match up with the end user demands. Undergoing lab tests for ensuring defined quality standards. original shell vial for Waters 96-position autosampler. manufactured from superior quality borosilicate glass. 0.15 or 0.20 mL limited volume insert

polypropylene snap/crimp micro vials combine the robustness of TPX PMP with the benefits of PP micro inserts.PP vial material was used for Ion analysis to avoid contamination by glass HPLC vials during analysis. polypropylene snap/crimp micro vials can be used in most standard gas and liquid chromatography autosamplers. These lightweight, economical vials are made from durable polypropylene which has good chemical resistance. Breakage is not an issue with plastic vials, and they are non-reactive with most sample chemistries. PP vials are ideal for samples where glass is not appropriate; as with samples that adhere to glass.

Autosampler vial can be divided into HPLC vial and GC vial. So Autosampler vial has different volume. Especially, some sample is rare. so the micro-insert is needed. No matter which autosampler vial you need, you should confirm the chromatography instrument, firstly. You can find your needed in Aijiren and you can also tell us your requirement, our technical engineer will give anwser.

Vial Volume: 1.5-2.0ml
Vial Material: Borosilicate Glass/Glass Type 1
Application: Lab consumables for analysis
Certification: ISO9001, SGS, COA
Vial Thread: Screw
Cap: Plastic open/solid cap
Septa: Non-slit, Pre-Slit, PTFE/Silicone

Item: Micro Insert for 9mm Autosampler Vial
Volume: 0.15-0.3ml
Color: Transparent
OEM: Available
Sample: Free
Certification: ISO9001:2015
Packing: 100pcs/pk
Brand Name: Aijiren
Place of Origin: China (Mainland)
Compatibility: 9mm HPLC Vials

Aijiren clear glass vial inserts, polypropylene vial inserts, and high recovery vials ensure you extract the maximum possible amount of your precious sample.
Material: Borosilicate Glass
Working Volume (mL): 0.3mL
Working Volume (μL): 300 μL
Bottom: Flat
Insert: Conical, base bonded, integrated insert

Aijiren can supply glass vial, such as autosampler vial, screw top HPLC vial, snap top glass vial and crimp finished headspace vial. You can also get micro-vial and micro-insert in aijiren shop. The micro-vial and micro-insert is used for chromatography system, too.

Polypropylene as a vial material is a good choice for protein analysis because normal borosilicate glass vials are known to absorb some types of analytes such as proteins, peptides, and amines.
Insert Volume: 0.3ml
Vial Thread: Screw
Vial Dimension: 12x32mm
Vial Color: Amber and Clear
Usage: Laboratory Analysis
Packing: 100pcs/pk

Micro vials are designed to assist in the consistent sampling of low-volume chromatography samples.
Diameter (Metric) Outer: 11.6 mm
Volume (Metric): 0.36 mL
For Use With (Application): GC, HPLC
Neck Style: Short Thread
Shape: Flat Bottom
Height (Metric): 32 mm

Micro Insert is used to ensure the most accurate and reliable analysis of your lab samples. The 250 μL Conical Bottom Vial Inserts are made of clear glass and suits for 9mm, 10mm, and 11mm vials.  Micro inserts, when used in conjunction with autosampler vials, allow for maximum sample recovery and easier sample removal because the conical shape decreases the surface area inside the vial. The precise design and sealing properties of micro insert vials prevent sample loss, evaporation, and contamination, preserving the integrity of analytes throughout the analysis process. Whether in pharmaceutical research, environmental analysis, or other scientific disciplines, micro insert vials empower researchers to obtain precise and accurate results with limited sample availability.

Item: 250uL Micro Insert for 9mm HPLC Vials
Volume: 0.25ml
Color: Transparent
OEM: Available
Sample: Free
Certification: ISO9001:2015
Place of Origin: China (Mainland)
Compatibility: 2ml HPLC Vials
Polyspring inserts are self-aligning and provide a cushion against needle contact

Micro vials are specially designed to collect micro-volume samples and minimize evaporation.
Two sizes are available
Tapered for high recovery of contents.
Work with Mininert sampling valves.

Micro vials are suitable for Agilent, AB Sciex, Brukers, Techcomp, PerkinElmer, ThermoScientifics, Shimadzu, Waters, CTC autosampler and other rotating or robotic arm samplers and autosamplers.

11mm Crimp Neck Conical micro-vial for laboratory chromatography experiment, the micro-vial size is 11.6x32mm. High quality glass vial for HPLC/GC analysis. 0.3 ml clear glass micro insert fixed in 2ml glass vial.Conical base insert vial can saving samples while during injection.Wide opening top for better needle injection. 2ml clear glass vial with 0.3ml intergrated vial, designed for valuable samples to save for testing use volume. Bottom fixed micro insert to keep the vial central vertical

Autosampler vial can be divided into HPLC vial and GC vial. So Autosampler vial has different volume. Especially, some sample is rare. so the micro-insert is needed. No matter which autosampler vial you need, you should confirm the chromatography instrument, firstly. You can find your needed in Aijiren and you can also tell us your requirement, our technical engineer will give anwser.

HPLC / GC autosampler vials, caps, septa, and inserts working as a whole to prevent sample degradation and loss of samples caused by evaporation. All components of 2ml autosampler vials from AirekaCells® are designed manufactured by the same level of product standard.

Polypropylene as a vial material is a good choice for protein analysis because normal borosilicate glass vials are known to absorb some types of analytes such as proteins, peptides, and amines.
Insert Volume: 0.3ml
Vial Thread: Screw
Vial Dimension: 12x32mm
Vial Color: Amber and Clear
Usage: Laboratory Analysis
Packing: 100pcs/pk

Item: 250uL Micro Insert for 9mm HPLC Vials
Volume: 0.25ml
Color: Transparent
OEM: Available
Sample: Free
Certification: ISO9001:2015
Place of Origin: China (Mainland)
Compatibility: 2ml HPLC Vials
Polyspring inserts are self-aligning and provide a cushion against needle contact

1.Micro-volume “Drop-In” Inserts for use with Standard 8-425 (8mm) Mouth Vials.
2.Compatible with all 2ml Screw Vials, 8-425 Thread
3.Center automatically with flat bottom and mandrel interior
4.Type I borosilicate glass

Customization:
Customized logo(Min. Order: 300 Packs)
Customized packaging(Min. Order: 400 Packs)
Usage: Laboratory Analysis
Logo: Customized Accepted
OEM: Available
Sample: Provided Freely
Packing: 100pcs/pk
Material: Borosilicate Glass

Aijiren 300ul micro-volume inserts, clear glass, flat bottom. better to use combined with 2ml HPLC vials for HPLC.  Flat base Sample Vials.
Made from advanced technology and excellent raw materials. Precise bottle neck size, ensure autosampler handle is correct. Fully compatible with various brands of automatic samplers. Strict quality control to ensure size consistency from batch to batch. Clear Glass Micro Insert is used to ensure the most accurate and reliable analysis of your lab samples. Micro inserts, when used in conjunction with autosampler vials, allow for maximum sample recovery and easier sample removal.

Item: 3 Types of HPLC Vial Insert for Autosampler Vials
Volume: 0.15-0.3ml
Color: Transparent
OEM: Available
Sample: Free
Certification: ISO9001:2015
Place of Origin: China (Mainland)
Compatibility: 9mm HPLC Vials
Polyspring inserts are self-aligning and provide a cushion against needle contact
Conical inserts with polymer feet are self-centering and have a cushion against needle penetration

Micro vials are designed to assist in the consistent sampling of low-volume chromatography samples.
Diameter (Metric) Outer: 11.6 mm
Volume (Metric): 0.36 mL
For Use With (Application): GC, HPLC
Neck Style: Short Thread
Shape: Flat Bottom
Height (Metric): 32 mm

9mm Screw conical micro-vial for laboratory chromatography experiment, the micro-vial size is 11.6x32mm.
High quality glass vial for HPLC/GC analysis. 0.3 ml clear glass micro insert fixed in 2ml glass vial. Conical base insert vial can saving samples while during injection. wide opening top for better needle injection. 2ml clear glass vial with 0.3ml intergrated vial, designed for valuable samples to save for testing use volum. Bottom fixed micro insert to keep the vial central vertical

Micro Insert is used to ensure the most accurate and reliable analysis of your lab samples. The 250 μL Conical Bottom Vial Inserts are made of clear glass and suits for 9mm, 10mm, and 11mm vials.  Micro inserts, when used in conjunction with autosampler vials, allow for maximum sample recovery and easier sample removal because the conical shape decreases the surface area inside the vial. The precise design and sealing properties of micro insert vials prevent sample loss, evaporation, and contamination, preserving the integrity of analytes throughout the analysis process. Whether in pharmaceutical research, environmental analysis, or other scientific disciplines, micro insert vials empower researchers to obtain precise and accurate results with limited sample availability.

Vial Volume: 1.5-2.0ml
Vial Material: Borosilicate Glass/Glass Type 1
Application: Lab consumables for analysis
Certification: ISO9001, SGS, COA
Vial Thread: Screw
Cap: Plastic open/solid cap
Septa: Non-slit, Pre-Slit, PTFE/Silicone

Amber 9mm HPLC Vials with Insert are universally suitable on most autosamplers, convenient in handling, and available in a broad selection of different cap colors and septum materials.

Aijiren clear glass vial inserts, polypropylene vial inserts, and high recovery vials ensure you extract the maximum possible amount of your precious sample.
Material: Borosilicate Glass
Working Volume (mL): 0.3mL
Working Volume (μL): 300 μL
Bottom: Flat
Insert: Conical, base bonded, integrated insert

1.Micro-volume “Drop-In” Inserts for use with Standard 9-425 (9mm) Mouth HPLC Vials.
2.Compatible with all 2ml Screw HPLC Vials, 9mm Thread
3.Center automatically with a flat bottom and mandrel interior
4.Type I borosilicate glass

Micro inserts, when used in conjunction with autosampler vials, allow for maximum sample recovery and easier sample removal because the conical shape decreases the surface area inside the vial.

9mm Short Thread Vial with integrated 0.3ml Micro-Insert, 32 x 11.6mm, Amber or clear glass, 1st hydrolytic class, label and filling lines, 100/pk
Aijiren 9mm glass vial with fused insert together eliminates movement of the insert. The fused insert also eliminates concerns about contaminants around the fused seam/space between the neck of the vial and the insert. Vials without graduation, all micro inserts are clear glass. Vials with integrated Micro-Insert are also available now in clear and amber glass. amber glass makes it compatible with sun-proof samples.

Conical glass inserts have a tapered bottom with pulled tips and are available with or without plastics polypropylene springs. The spring acts as a shock absorber during needle penetration and raises the insert above the bottom of the vial, allowing greater sample recovery.

Item: Micro Insert for 9mm Autosampler Vial
Volume: 0.15-0.3ml
Color: Transparent
OEM: Available
Sample: Free
Certification: ISO9001:2015
Packing: 100pcs/pk
Brand Name: Aijiren
Place of Origin: China (Mainland)
Compatibility: 9mm HPLC Vials

9mm screw autosampler vial with micro-insert for chromatography analysis has been widely recognized. This micro-insert has different shape. Cone bottom and Flat bottom micro-insert are very common. You also saw the micro-insert with spring support.

Aijiren vial inserts are the perfect fit for HPLC and GC instrument platforms across a wide variety of applications, including pharmaceutical, environmental, energy and fuels, forensics, materials science, biopharmaceutical, proteomics, and metabolomics.
Material: Borosilicate Glass
Payment: 100% T/T in advance
Certificate: ISO9001:2015
Brand Name: Aijiren
Packing: 100pcs/pk

polypropylene snap/crimp micro vials combine the robustness of TPX PMP with the benefits of PP micro inserts.PP vial material was used for Ion analysis to avoid contamination by glass HPLC vials during analysis. polypropylene snap/crimp micro vials can be used in most standard gas and liquid chromatography autosamplers. These lightweight, economical vials are made from durable polypropylene which has good chemical resistance. Breakage is not an issue with plastic vials, and they are non-reactive with most sample chemistries. PP vials are ideal for samples where glass is not appropriate; as with samples that adhere to glass.

Flat bottom glass inserts have the largest capacity and are the most economical inserts. These inserts are cylindrical in shape with a flat bottom.Aijiren is the leading supplier of Flat bottom glass inserts since 2007.

Usage: Laboratory Analysis
Logo: Customized Accepted
Trademark: Aijiren
Origin: China
OEM: Available
Sample: Provided Freely

Item: Micro Insert Suit for 9mm HPLC Vials
Volume: 0.25ml
Color: Transparent
OEM: Available
Sample: Free
Certification: ISO9001:2015
Place of Origin: China (Mainland)
Compatibility: 9mm HPLC Vials
Polyspring inserts are self-aligning and provide a cushion against needle contact
Conical inserts with polymer feet are self-centering and have a cushion against needle penetration

Micro vials are specially designed to collect micro-volume samples and minimize evaporation.
Two sizes are available
Tapered for high recovery of contents.
Work with Mininert sampling valves.

Aijiren polypropylene screw micro vials can be used in most standard gas and liquid chromatography autosamplers. The PP micro vial is constructed from high-quality polypropylene, a chemically inert and durable plastic material known for its excellent chemical resistance. This material ensures that the vial does not react with or contaminate the sample. The vial features a threaded screw neck, which allows for a secure and airtight seal when the cap is screwed onto the vial. This feature is crucial to prevent sample evaporation and contamination. Aijiren PP vials combine the robustness of TPX PMP with the benefits of glass or PP micro inserts.

Micro-vial volume is 0.3ml. this micro-vial is used for chromatography instrument. There are some expensive sample to analysis. To the needle inject the sample, so this vial is needed. Compared with micro-insert, micro-insert is more expensive. But the micro-vial is compatible with most instrument.

Micro inserts, when used in conjunction with autosampler vials, allow for maximum sample recovery and easier sample removal because the conical shape decreases the surface area inside the vial.

Conical Inserts from Aijiren are designed to assist in the consistent sampling of low-volume chromatography samples. Micro Insert is used to ensure the most accurate and reliable analysis of your lab samples. The 150 μL Conical Bottom Vial Inserts are made of clear glass and suits for 8-425 vials. Micro inserts, when used in conjunction with autosampler vials, allow for maximum sample recovery and easier sample removal because the conical shape decreases the surface area inside the vial. Analysts can use insert vials to achieve greater control over sample introduction, reduce contamination risk, improve data quality overall, ensure consistent injection volumes with increased peak shapes, optimize separation efficiency, and enhance chromatographic performance.

11mm Crimp Neck Conical micro-vial for laboratory chromatography experiment, the micro-vial size is 11.6x32mm. High quality glass vial for HPLC/GC analysis. 0.3 ml clear glass micro insert fixed in 2ml glass vial.Conical base insert vial can saving samples while during injection.Wide opening top for better needle injection. 2ml clear glass vial with 0.3ml intergrated vial, designed for valuable samples to save for testing use volume. Bottom fixed micro insert to keep the vial central vertical

Fused-insert sample vials work with both snap caps and crimp caps. These small samples fused-insert vials work with both snap caps and crimp caps. 11mm Glass Crimp Neck Vials with Fused Inserts are ideal for handling small-volume samples while delivering low residual volume. 11mm Glass Crimp Neck Vials with Fused Inserts offers the simplicity and functionality of typical micro vials at a fraction of the cost. 0.3 ml clear glass micro insert fixed in 2 ml glass vial. Bottom fixed micro insert to keep the vial central vertical. Vials with integrated Micro-Insert are also available now in clear and amber glass. amber glass makes it compatible with sun-proof samples. Their glass Micro-Insert is absolutely centered in the plastic mold and pressed firmly against the septa due to its slightly exceeding edges.

Zhejiang Aijiren Technology, Inc. is a global supplier of life-science, chemistry, laboratory consumables, etc. Our major products are high performance liquid chromatography & gas chromatography consumables such as Chromatography Autosampler Vials with closures, inserts, crimper and syringe filters, etc; Water analysis consumables such as COD test tube.

Micro vials are suitable for Agilent, AB Sciex, Brukers, Techcomp, PerkinElmer, ThermoScientifics, Shimadzu, Waters, CTC autosampler and other rotating or robotic arm samplers and autosamplers.

For some applications Polypropylene HPLC Vials are not suitable due to their composition and their chemical properties. Amongst these are heavy metal analysis, water and protein analysis, atomic absorption, capillary electrophoresis (CE) and ion chromatography (IC). For all these cases high purity polypropylene vials with 0.3 mL, 0.7 mL and 1.5 ml in transparent and amber are available.

There are screw top autosampler vial, snap Top HPLC vial and glass storage vial. All of those glass vial are often needed in laboratory. The glass vial can supply in Amber and Clear color. Borosilicate 3.3 Glass material made the Glass vial.

Finding suitability to be used over a wide temperature range, these 1ml Shell vials come extensively tested so as to perfectly match up with the end user demands. Undergoing lab tests for ensuring defined quality standards. original shell vial for Waters 96-position autosampler. manufactured from superior quality borosilicate glass. 0.15 or 0.20 mL limited volume insert

9mm Screw conical micro-vial for laboratory chromatography experiment, the micro-vial size is 11.6x32mm.
High quality glass vial for HPLC/GC analysis. 0.3 ml clear glass micro insert fixed in 2ml glass vial. Conical base insert vial can saving samples while during injection. wide opening top for better needle injection. 2ml clear glass vial with 0.3ml intergrated vial, designed for valuable samples to save for testing use volum. Bottom fixed micro insert to keep the vial central vertical

Item: HPLC Vials Insert
Volume: 0.15-0.3ml
Color: Transparent
OEM: Available
Sample: Free
Certification: ISO9001:2015
Place of Origin: China (Mainland)
Compatibility: 2ml HPLC Vials

Micro inserts Packing: Economy Package and General Package for choose. Neutral carton outside, pallet is available to protect quality better.
OEM packing is also available.

9mm Screw conical micro-vial for laboratory chromatography experiment, the micro-vial size is 11.6x32mm.

The choice of autosampler vials may seem much less important compared to the significance chromatography instruments many laboratories use. However, the wrong choices of HPLC or GC vials, caps, septas and inserts might well lead to lower experiment productivity and reproducibility or even mechanical damage to the autosampler.

Aijiren is the leading supplier of chromatography consumables, can offer hplc vials,hplc syringe filter, EPA VOA vials, and some other test tubes.
Any requirement for chromatography consumables, please contact us.

Vial Dimension: 12x32mm
Vial Volume: 1.5-2.0ml
Cap: Plastic open/solid cap
Septa: Non-slit, Pre-Slit, PTFE/Silicone
Characteristic: Consistency at quantification levels
Highly reproducible for samples >120µL
Long-term sample stability for most analytes
High solvent compatibility for mainstream HPLC and GC applications
Compatible with standard HPLC and GC autosamplers

250µL Flat Bottom Glass Inserts for Chromatography Vials. These Flat Bottom Glass Inserts are designed to be used in 2mL standard opening crimp top and screw thread vials. They represent an economical alternative to the conical limited-volume inserts. Clear Glass Micro Insert is used to ensure the most accurate and reliable analysis of your lab samples. Micro inserts, when used in conjunction with autosampler vials, allow for maximum sample recovery and easier sample removal. The 250µL Glass Flat Bottom Inserts make an excellent choice to daily chromatographic experiments in the lab combining the highest quality and consistent results with low cost. A must-have for your research.

Aijiren can supply glass vial, such as autosampler vial, screw top HPLC vial, snap top glass vial and crimp finished headspace vial. You can also get micro-vial and micro-insert in aijiren shop. The micro-vial and micro-insert is used for chromatography system, too.

Micro inserts Packing: Economy Package and General Package for choose. Neutral carton outside, pallet is available to protect quality better.
OEM packing is also available.

Items: Micro Insert vials
OEM: Available
Sample: Provided Freely
Packing: 100pcs/pk
Material: Borosilicate Glass
Borosilicate Glass material provides higher quality material that is more resistant to thermal shock
The integrated insert supports samples of the highest purity and sensitivity
Amber color provides for an increased shelf life optimal for storage of samples of light-sensitive samples
The highest quality ISO9001:2015 certification in the industry ensures the most accurate analysis of samples

0.3 ml clear glass micro insert fixed in 2ml glass vial, designed for valuable samples to save for testing use volume

11mm crimp top vials have a volume of 0.3mL and provide an excellent seal for long term sample storage and analyses involving high volatile solvents. Standard vials for GC and HPLC applications.2ml clear glass vial with 0.3ml integrated vial, designed for valuable samples to save for testing use volume. Vials with integrated Micro-Insert are also available now in clear and amber glass. amber glass makes it compatible with sun-proof samples. Their glass Micro-Insert is absolutely centered in the plastic mold and pressed firmly against the septa due to its slightly exceeding edges. The highest quality ISO9001:2015 certification in the industry ensures the most accurate analysis of samples.

Item: 250ul HPLC Vial Insert
Volume: 0.25ml
Color: Transparent
OEM: Available
Sample: Free
Certification: ISO9001:2015
Place of Origin: China (Mainland)
Compatibility: 2ml HPLC Vials
Polyspring inserts are self-aligning and provide a cushion against needle contact

9mm Screw conical micro-vial for laboratory chromatography experiment, the micro-vial size is 11.6x32mm. High-quality glass vial for HPLC/GC analysis. 2ml clear glass vial with 0.3ml integrated vial, designed for valuable samples to save for testing use volume. Bottom fixed micro insert to keep the vial central vertical. Vials with integrated Micro-Insert are also available now in clear and amber glass. amber glass make it compatible with sun-proof samples. Their glass Micro-Insert is absolutely centered in the plastic mold and pressed firmly against the septa due to its slightly exceeding edges. Standard vials for GC and HPLC.

Micro Insert is used to ensure the most accurate and reliable analysis of your lab samples. Micro-inserts are manufactured of clear glass. Micro inserts, when used in conjunction with autosampler vials, allow for maximum sample recovery and easier sample removal because the conical shape decreases the surface area inside the vial.
Micro inserts can be used with screw tops, crimp tops, or snap-top vials. All conical styles of inserts are offered with the traditional pulled point as well as the improved mandrel point. Pulled point inserts are more economical, but mandrel point inserts provide a more pointed and uniform tip that enables better sample recovery. Micro-inserts can be used on all 1.5ml vials. Effectively relieves the pressure of the syringe. PolySpring inserts are self-aligning.