Hurst Roll/Control, Line/Loc 12-volt Solenoid ValveThe is the legendary Hurst Roll Control, Line Loc that drag racers have been using for decades to heat up the tires in the burnout box for maximum traction before making a pass down the track is also used to provide positive locking action to the front wheels of race cars, reducing the chance of "Rolling the Lights" when staging. This universal solenoid allows you to design, fabricate and build the valve into your braking system the way you want,