Eco Master Cylinder - With Reservoir

A hydraulic handbrake acts directly on the rear calipers. It locks the axle without using cables, providing a crisp, repeatable lockup — something the original cable can no longer do once the car gains weight or grip.

The master cylinder bore is not a minor detail. The smaller it is, the faster pressure rises for the same lever effort, but the longer the stroke becomes. A 0.75" bore suits most stock rear calipers; a larger bore is reserved for calipers with large pistons.