The FOX 029-03-315 is a replacement O-ring seal with a 0.210 inch cross-section and a 0.787 inch inside diameter, designated as N-70 and intended for static sealing. Rings in this class sit in a groove and stop shock oil from leaking at a joint where the two surfaces do not move against each other. Installing a fresh ring during a rebuild costs far less than replacing the damper, and it restores a clean seal once an old ring has hardened, flattened, or taken a permanent set.
Choose this seal when rebuilding a FOX shock or servicing a static oil joint, and check the old ring's dimensions with calipers before ordering. A ring that is even slightly off in cross-section or inside diameter can seat poorly and weep fluid under pressure, so matching the 029-03-315 designation exactly matters more than the price difference. Searchers looking for a FOX -315 O-ring, a 0.210 C.S. x 0.787 ID shock seal, or an N-70 static O-ring for FOX shock rebuilds will find this listing matches that spec.
