Ptfe Silicone Septa - Thomas Scientific. Ptfe Silicone Septa found in: 11mm Snap Caps (with PTFE/Silicone Septa/PTFE), distributor to place orders for Aijiren Technologies products. Septa for GL Caps, Silicone and Silicone/PTFE, Ace Glass - VWR. PTFE/Silicone Septa (T/S) has high-quality, low background/blank value, 100% synthetic pure silicone