حلقات O من PTFE 0.139" CS × 3.109" ID | AS568-235 | داش 235 | صلابة 23 (300/عبوة)

The 23 durometer makes these PTFE o-rings surprisingly flexible for installation, yet they held a perfect seal in my high-temp test. Really happy with the consistent sizing across the whole pack of 300.

I needed a seal that could handle constant thermal cycling from liquid nitrogen temps up to steam sterilization, and these PTFE o-rings have held up perfectly through dozens of cycles so far. The 23 durometer gives them just enough flexibility to seat easily without cracking.

The -350°F lower limit is exactly what I needed for a cryogenic seal application, and these PTFE rings haven't shown any brittleness. The 23 durometer feels noticeably softer than the standard 75-90 stuff I've used before.