Thermo Scientific™ National 20mm Septa for Headspace Vials are designed for use with unlined 20mm crimp seals
PTFE/red rubber septa are resistant to coring and offer good resealing characteristics Gray butyl is an economical septum for low temperature applications PTFE/gray butyl septum provides increased chemical resistance PTFE/silicone septa offer excellent chemical resistance, resealing characteristics and low background
Use aluminum foil/silicone septa in extreme high temperature applications PurePak™ PTFE/silicone septa are packed in glass jars to maintain purity up to the point of use