UK wide opening headspace gas chromatography manufacturer 2022 - 04 - 20 Autosampler Vials, Caps, and Closures 2021 - 05 - 10 Chromatography Aijiren Tech™ 20 mm Headspace Vials, Septum, and Caps Headspace vials are available in clear or amber glass with a round or flat base, a crimp seal with a beveled or square edge finish, or with a screw-thread finish.