Square O-Ring Kit - 2.75

The Wilwood Square O-Ring Kit - 2.75 is a precision brake caliper rebuild component engineered for mechanics and brake system enthusiasts who demand reliable sealing in high-performance braking applications. This 2.75-inch square o-ring kit restores critical hydraulic integrity to Wilwood brake calipers, making it essential for anyone rebuilding or servicing competition-grade braking systems. Whether you're maintaining a race vehicle, street performance machine, or restoring a brake system to factory specifications, this kit addresses the root cause of brake fluid leakage and loss of stopping power.

Square o-rings are specifically designed to create superior hydraulic seals within brake caliper pistons, accommodating the high-pressure demands of modern braking systems while resisting degradation from brake fluid exposure. The 2.75-inch diameter specification matches Wilwood's popular piston sizes, ensuring precise fit and optimal sealing performance without over-compression or gaps that compromise braking consistency. These elastomer seals prevent microscopic fluid weeping that can accumulate into brake fade, spongy pedal feel, and catastrophic system failure—common problems that arise when original o-rings deteriorate from heat cycling, age, or aggressive fluid chemistry.

Professional rebuilds of Wilwood four-piston and six-piston calipers depend on this kit to restore factory-equivalent sealing without replacing entire assemblies. Technicians and DIY builders installing Wilwood brake systems for track use, off-road racing, or high-horsepower street applications will find this replacement kit indispensable for preventive maintenance or emergency repairs. Compact at 0.13 lbs and easily stored, the kit ships ready for immediate installation during your next caliper service interval.