حلقات O من فيتون FKM مقاس 0.21" CS × 4.475" ID | AS568-349 | داش 349 | صلابة 90 (14 / عبوة)

Needed to replace a worn seal in a hydraulic setup that sees some serious heat, and these Viton rings handled the 300°F service without any softening. The 90 durometer hardness made them feel stout during installation, and the 14-pack gives plenty of spares for the price.

The cross-section on these is noticeably thicker than the standard o-rings I've used before, so they feel much more durable when seated in the groove. I put them on a hydraulic fitting that sees constant heat, and they sealed perfectly on the first try. Exactly what I needed for a high-temp applicat

That 400°F rating is the main reason I bought these—my pneumatic valve gets hot enough to melt standard Buna-N rings in a week. After swapping to this Viton set, no leaks so far. The 90-durometer feel is noticeably stiffer than what I used before, which is exactly what the application needed.