11. Aijiren Tech crimp top headspace vials are available in a flat or round bottom style, with clear or amber glass. 6ml clear crimp-top headspace vial, flat bottom, 22*38mm (6ml karl Aijiren Tech vial), 5.0 type. 20ml clear crimp-top Headspace vial, w/write-on spot, flat bottom, 22.5*75mm, 5.0 type. 20ml clear crimp-top Headspace vial, w/write-on