Glass Vial 4 Ml found in: 10 ml Vacule With 22-350 Cap, Screw Cap Sample Vial, E-C Vials w / Rubber Lined Caps, Clear, 4 ml, 4 mL S/T Vacule, Type I Clr,.. these vials are assembled with the following materials: Type 1 borosilicate glass, PTFE/silicone septa, and a polypropylene cap. PTFE/silicone septa, and a polypropylene cap.