Glass Vials 10 ml and 20 ml Crimp Neck Content: 100 pcs. / pack. alu cap 10 mm centre hole; silicone white/PTFE beige; 3.2 mm thick; 45° shore A. 20mm Aluminum cap Crimp top headspace vial. According to different material, the 20mm crimp headspace vial can be divided into two types. One is domestic borosilicate, the other one is USP type1. 20