حلقات O من مطاط النتريل بونا-إن | قطر داخلي 0.662 بوصة × قطر مقطع 0.21 بوصة | AS568-313 | داش 313 | صلابة 90 (400 / عبوة)

I've been using these o-rings to rebuild a few pneumatic cylinders, and the 90 durometer material holds up much better against abrasion than the standard 70 stuff I used before. The inner diameter of 0.662" fit perfectly on the piston grooves without any stretching or distortion.

Had to replace a handful of seals on a hydraulic line that kept weeping, and the 0.662" inner diameter fit perfectly. The 90-durometer rubber feels noticeably firmer than the standard 70 stuff I've used before, so I'm hoping these hold up better under pressure.

The 90 durometer rating on these o-rings gives them a reassuring firmness for high-pressure applications. I used a pack to rebuild a pneumatic cylinder, and the seal held perfectly through multiple cycles. Very consistent sizing across all 400 pieces.