10mm chromatography vial septa on stock China-aijiren HPLC. HPLC 10MM Screw Neck PP Cap. We provide the protection of PTFE and the resealing ability of silicone with our septa and seals to fit our autosampler crimp top vials. This seal includes a two sided PTFE septa with silicone in the center. 10mm Screwo Top PP Caps.