Preassembled aluminum crimp caps for all 20 mm Headspace GC autosampler vials, including Aijiren, Hewlett Packard, CTC, PerkinElmber, Tekmar, and LEAP vials. Standard center hole with gray PTFE-faced black molded butyl rubber septa, with sealing ring for exceptional seal. Recommended for use from -40 to 120° C. 1,000 Caps Per Case