Residual Valve

 
***Actual product may vary from pictures***
Hotrod Universal Residual Check Valve - 2lbs & 10lbs
A residual valve acts like a one-way or check valve to maintain brake system pressure to eliminate the problems of a spongy pedal. When your master cylinder is frame mounted.
This 2 PSI residual valve is installed inline between the master cylinder and disc brake calipers to keep 2 PSI of residual pressure at the caliper after the brake pedal is released. 
2 PSI Valves are used with Disc Brakes depending on your lines you may need 2 one for each front line going to the calipers.
10 PSI residual valve is installed inline between the master cylinder and drum brake to keep 10 PSI of residual pressure at the wheel cylinder after the brake pedal is released. 
Square Style
3/8-24 Fitting Size