The 18mm Screw Top Headspace Vial produced by Aijiren is made of high-quality borosilicate hydrochloric acid glass, which can withstand high temperatures and is not easily deformed, and is extremely inert. And the tightness guaranteed by Screw’s caliber prevents the gas from overflowing during gas chromatography. Septa uses double-sided material that is not easy to deform, and the sampling needle is not easy to fall off when pierced.