حلقات O من HNBR CS 0.21" × ID 3.85" | AS568-344 | داش 344 | صلابة 80 (10 / عبوة)

The sealing surface feels spot-on for a 3.85" bore, and the 80 durometer has just enough firmness to seat firmly without fighting you. Running them at 250°F for a week straight with zero leaks so far, which beats the last batch I tried.

Finally got around to replacing the worn seal in my pneumatic cylinder, and these o-rings fit perfectly on the first try. The 80 durometer feels noticeably stiffer than the old ones, which should hold up well under pressure.

I've been using these for a hydraulic seal and the -40°F to +300°F range gives me confidence they'll hold up. The 3.85" inner diameter fit perfectly into the groove without any wrestling.