11mm septa

The crimp caps of the vials is made of aluminum for crimping and sealing; plastic (polyethylene, polypropylene or phenolic resin) for non-crimping and sealing. The cap gasket is a septum material that is pierced by a syringe needle to extract a sample from the vial. The cap liner sheet has various configurations and is also made of various materials.

11mm Natural Snap-top PE Caps, 6mm Centre Hole
White PTFE/Red Silicone Septa 11*1mm
for 11mm Glass Snap Top Vials

Hplc Vials Septum
Red PTFE White Silicone Septum
Septum Size: 11*1mm

PTFE is the most inert but its poor resealability making it unsuitable for multiple injections or storage. For layered septa such as PTFE/silicone the chemical resistance of the septa is that of PTFE until the septum is punctured. Once punctured, the silicone layer is exposed and able to react with sample/solvent so the chemical resistance of silicone should be considered when using these septa.