Vial. (100/pk) CrossLab headspace crimp top vial, 20 mL, amber, round bottom. Cap. (100/pk) CrossLab cap, headspace crimp top, 20 mm, silver aluminum, tan PTFE/silicone septa. For any headspace applications using a pressure over 45 PSI, use of a safety release cap is strongly recommended to prevent damage to the vial.