White PTFE/White Silicone Septa, 20mm Crimp-top Aluminum Cap, 9.5mm Centre Hole. SCS201201. White PTFE/White Silicone Septa, 20mm Pressure Release Headspace Aluminum Cap, 9.5mm Centre Hole. SC209204. White PTFE/Blue Transparent Silicone Septa, 20mm Crimp-top Aluminum Cap, 10mm Centre Hole for 6ml Karl Aijiren Tech Vials. SBC201202