Thermo Scientific™ 9 mm septa are available in PTFE/red rubber, PTFE/silicone or red PTFE/white silicone/red PTFE to suit a variety of applications.Septa are available in a variety of materials and thicknesses. PTFE Natural Rubber are moderately priced seals for GC and HPLC with good chemical properties. They are ideal for multiple injections due to high resealability, but not as easy to