FREUDENBERG – Silicone Stoppers

For tight, reliable seals


  • Packaged 12 per zip bag in crush-resistant boxes
  • Autoclavable
  • contain no peroxide catalysts





HelixMark® pharmaceutical-grade Silicone Stoppers are ideal for tight, reliable sealing glass tubes, vials, and flasks.


These platinum-cured silicone stoppers have full traceability to raw materials, contain no peroxide catalysts, and are autoclavable. Biologically safe, they can be used with glass, metal, or plastic vessels.

In our clean room, we can add stoppers in assemblies. Stoppers, caps, and inserts for True Unions, with or without tubing, are available.

The stoppers come in a variety of sizes and have multiple capabilities such as pre-drilled holes and the ability to be added to assemblies. Available in 14 standard sizes. We also offer stoppers with pre-drilled holes.

Technical information

CertificationsISO 10993-1, FDA 21 CFR 177-2600, USP Class VI, EP 3.1.9
Typical hardness50 shore
Clean Room CompatibilityISO Class 8 cleanrooms
Dimensions14 standard sizes, top diameter from 13 mm to 68 mm