Description 87039550 Brake Caliper Piston Phenolic 70MM Brake Piston, Includes: (1) Piston. Four (4) ref. 5 are Required for (1) Caliper. Steel Pistons are no longer available as new service replacement. Fits New Holland Bale Wagon models: BW28 with front and rear 70MM Quadraulic Phenolic Piston 7/16″-24 Inlet H9880 with front and rear 70MM Quadraulic Phenolic Piston 7/16″-24 Inlet