Whether you call them roll controls, line locks, or whatever, Hurst Roll Controls keep can keep your manual or auto car out of the staging lights until you're ready to launch. Controlled by a solenoid valve attached to a switch on your shifter, roll controls keep you from rolling by locking your front or rear brakes. When you hit the switch, your brakes are unlocked and you're ready to hit the throttle. Rigorous testing has proved a 1/100,000th of a second release time, and vibration tests have surpassed 30 Gs without mechanical failure. Each roll control comes with a rebuildable stainless steel solenoid valve, indicator light, inline fuse holder, and complete instructions. Hurst Roll Controls give you one less thing to worry about when you're staging.