National Scientific headspace vials are manufactured to provide uniform glass thickness which insures even heat distribution for consistent sampling reliability. All National Scientific headspace vials meet or exceed OEM instrument manufacturer's specifications. National Scientific Headspace vials are available in 6mL, 10mL, 20mL and 27mL versions. Use Tin plate seals with magnetic pick autosamplers. Pressure release seals are designed to open when internal pressures exceed 3.0±0.5 bar, protecting equipment during analysis of highly volatile samples. Flat bottom vials are used for Agilent and Carlo Erba autosamplers. Those with conical bottom are specific for Perkin-Elmer, Tekmar and Varian/Bruker. - PTFE/rubber septum are resistant to solvents and within a temperature range from -40ºC to +100ºC. - PTFE/silicone septum is an excellent option for volatiles. Great chemical compatibility. Suggested temperatures from -60ºC to +200ºC. - PTFE/molded gray butyl septum have a central part made of PTFE and an external part of butyl. The central part provides chemical compatibility and the external better sealing and adaptation. Temperature range goes from -20ºC to +125ºC.