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Septum, PTFE/Butyl

PTFE/rubber (butyl (Pharma-Fix)), diam. × thickness 20 mm × 0.135 in., pkg of 100 ea

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Septa, PTFE faced butyl


PTFE/rubber (butyl (Pharma-Fix))


Pharma-Fix septum


pkg of 100 ea


13 mm

diam. × thickness

20 mm × 0.135 in.


for use with 20mm crimp seal, 22mm hole cap, 22mm solid cap

General description

PTFE-fused septa are suitable to overcome the degradation, which happens due to prolonged high temperatures, commonly observed in silicone rubber septa. The degradation results in baseline drift and additional peaks. It is generally fixed with the PTFE face towards the column packing.


PTFE-faced butyl septa may be used for headspace vials to assess sampling efficiency and breakthrough of methyl bromide on activated charcoal.
Septum may be used to seal vial during collecting urine samples for unmodified benzene analysis using HPLC method.

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