8mm Gold Aluminum Vial Seals with Teflon Septa, pk 100 Requires our crimper 08001. 8mm PTFE Teflon® /Silicone Septa aluminum vial seals - for critical forensic analysis, trace elements analysis, internal standards and chromatography applications. 8mm aluminum seal with 45 Durometer rating PTFE / Silicone septa septum.