This item is an exact reproduction disc brake hold off valve. This valve was used to hold off pressure to the rear brakes so the front brakes would go on a split second before. This was also considered a correction valve for the 1970 model year. During extreme braking conditions, this valve prevented the car from getting sideways and evened out braking loads. This valve is located at the rear of the car, mounted to the back cross member close to where the rubber brake hose attaches through the frame. In 1970, these cars had three valves that made up the disc brake system. The valves include: above hold off valve, distribution block, and round golf ball valve. In 1971, these three pieces were combined into one valve which simplified the system. This item is an exact reproduction featuring a brass body, the correct bracket, phosphate plating and working insides. You will also find with current manufacturing procedures, the reproduction has no tool stamping marks and the edges of the part are much cleaner than the original.