Square O-Ring Kit - 1.12

The Wilwood Square O-Ring Kit 1.12 (part number 130-2579) is a precision brake caliper rebuild kit engineered for high-performance hydraulic brake systems. This o-ring set is designed specifically for 1.12-inch Wilwood pistons and serves as the critical sealing component in caliper maintenance and restoration. Technicians and enthusiasts working on brake system rebuilds rely on this kit to restore proper hydraulic integrity and prevent fluid leakage across the piston bore.

The square o-ring profile provides consistent sealing pressure against the caliper bore wall, a critical design feature for maintaining brake line pressure and preventing air infiltration during brake system operation. O-rings are consumable wear items that degrade over time due to thermal cycling, fluid exposure, and mechanical compression—particularly in high-performance driving scenarios where brake temperatures exceed standard operating ranges. This kit includes the necessary rubber seals to restore factory specifications and ensure repeatable brake response after caliper disassembly and inspection.

Wilwood O-ring kits are used by brake technicians performing caliper rebuilds on racing vehicles, heavy-duty trucks, and performance platforms where factory or aftermarket Wilwood brake systems are installed. Whether addressing brake fade from a track day, restoring calipers after extended storage, or performing preventive maintenance, this 1.12-inch square o-ring kit provides the exact sealing components needed to restore hydraulic performance. Proper o-ring replacement during caliper service is essential for maintaining brake reliability and safety—a step no serious brake system rebuild should skip.