I had best luck with the blue EPDM O-rings I have purchased from WASDkeyboards.com.
Prior to my currently installed WASDkeyboards rings, I had purchased some black (approx. 2mm thick) and red (1mm thick) O-rings from Amazon. Those Amazon O-rings weren't made of EPDM.
Comparing to O-rings, purchased from Amazon, WASDkeyboards rings are being squishy and elastic and not as hard, they also don't split at all, but vast majority of both: black and red ones, purchased from Amazon DID SPLIT after a few months of use
![Sad :(](https://cdn.geekhack.org/Smileys/solosmileys/sad.gif)
Is this because I tend to bottom out hard? You see: I had learned to touch-type while serving in the Soviet Army, using Soviet-era telegraph machinery, that needed to be banged onto hard
![shocked :eek:](https://cdn.geekhack.org/Smileys/solosmileys/shocked.gif)
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I guess that the material Amazon O-rings were made of isn't elastic enough to absorb this repetitive stress applied by a Russian telegraphist?
![Cheesy :D](https://cdn.geekhack.org/Smileys/solosmileys/cheesy.gif)
I attribute this to the material WASDkeyboards O-rings are made of: EPDM, also known as EP, EPT, EPR, EPM or Ethylene-propylene
![Thumbs up! :thumb:](https://cdn.geekhack.org/Smileys/solosmileys/thumbsup.gif)
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