PTFE Faced Silicone Septa for GL45 Open Top PBT Screw Cap,OD: 43mm,Pack of 5 (GL45 PTFE Faced Silicone Septa)

On my second set, Great washer for GL45 caps. Takes a little longer to arrive but worth the wait

These things are awesome it's great having easy to assemble ptfe guard in place instead of using cardboard and plummers tape

Work great for a minute. If you tighten the lid more than just snug they get cut and then are useless. They don't last near long enough at 3 dollars apeice. Get a sheet of Teflon instead and cut them out. It's way cheaper and they last longer

Took a while to arrive but sometimes the GL45 glass does not come with seals and is nice to have these around. Allows me to buy lower prices glass and don't have to worry about leaks.

Pieces melted during heating

These fit the GL45 lids perfectly and make a huge difference in the sealing of the tops. They are pressure cooker safe, I sterilized at 15 psi for 30 minutes without any issues. The tops seal much better with these in place. I feel much safer using these inserts knowing my regents are now protected from any foreign bacteria. The lids are a little harder to twist down with the insert the first time but after you crank them down the insert fits into place better and it works like it was made for it.

These fit nicely in GL45 caps for reagent bottles and after short bit of testing seem to seal well and prevent leakage. I've only tested it with water so far though. Please be mindful of which compounds and solvents are compatible with silicone rubber. These will work great for my application though.

They fit the cap extremely well, i will know how good they are in anywhere from 6 months to a year since thats how long i was able to store the chemical last time before the lid failed.