Wilwood's Combination Parking Brake (CPB) Hydra-Mechanical Caliper uses hydraulic pressure for stopping and a mechanical locking mechanism for a parking brake. This redesigned unit provides new options for drum brake conversions and disc upgrades on rear axles that are not conducive to internal shoe systems. This caliper, when matched with the correctly proportionate rotor diameter, provides balanced bias and brake performance for use in conjunction with front wheel brake upgrades.