Wilwood caliper piston seal square ring kit, 6-piston front (1.38"/1.00"/1.00")

Replacement square rings for Wilwood caliper piston seals. As the name implies, these have a square cross section so you can't use generic o-rings. Kit includes enough for one Wilwood caliper with 1x1.38" and 2x1.00" pistons. In the kits we sell, that's: - Dynapro 6A front (aka Big Mama Jama) - Dynapro 6 front (no longer used in FM brake kits)