The Martin Custom Products Brake Caliper Rebuild Kits repairs the 1375 Standard Cast or Billet Brake Calipers. 

The kit includes two pistons and 2 O-rings that will restore your brake's performance as if they were brand new. We recommend checking your pistons and o-ring after each time you replace brake pads and when your braking is no longer firm and starts to feel spongey.

Piston Diameter: 1-3/8”