Brake Metering Valve

metering valve
A valve positioned in the hydraulic line to the front brakes, on some cars with front disc and rear drum brakes. It prevents the disc brakes from applying until after the rear brake linings contact the drum.
Valve which allows very presice flow regulation

brake
Make a moving vehicle slow down or stop by using a brake
stop travelling by applying a brake; "We had to brake suddenly when a chicken crossed the road"
any of various ferns of the genus Pteris having pinnately compound leaves and including several popular houseplants
a restraint used to slow or stop a vehicle