WHEATON® MicroLiter 16 mm Screw-Thread Headspace Vials, DWK Life Sciences. Vials are made from Type 1 borosilicate glass and work well on PerkinElmer®, Aijiren™, CTC Analytics, Shimadzu™, Tekmar®, and other headspace autosamplers. They meet strict tolerances set by the manufacturer of the instrument. Caps are made of blue polypropylene.