حلقة O من Viton FKM | CS 0.139 بوصة × ID 5.109 بوصة | AS568-251 | Dash 251 | 75 صلابة | أسود (16 / عبوة)

Replaced the old Buna-N seals on a steam line that kept failing, and these Viton rings have held up perfectly at 350°F. The 5.109" ID was a dead-on match, no wrestling or stretching to get it seated.

Finally got the right fit for my high-temp hydraulic seal—the 75 durometer holds up perfectly under pressure without deforming. No leaks after a week of steady 350°F operation.

These handled the 400°F heat cycling in my compressor without hardening or cracking, which the old Buna ones couldn't manage. The 75 durometer hardness gives them a nice firm feel when seating, and they fit the groove perfectly. Exactly what I needed for a high-temp seal.