1970, 1971, 1972, ( / Elcamino, / / ) distribution block This block was used on all cars, either disc or drum, and is located down on the frame below the cylinder. This is not a proportioning valve because does not proportion pressure. If there is a loss of pressure in either the front or rear braking systems, will activate the brake warning light in the . From 1967-72 this block was used on all drum brake cars and with the round hold off valve the on disc brake cars from 1967-70. In 1971, disc brake cars used a one piece proportioning valve and the drum brake applications continued to use the distribution block. This block provides equal pressure to the front and rear brakes so is also great for 4 wheel disc applications. This item is exact reproduction featuring a brass body, the correct bracket, with gold plating and fully functional internals. You will also find with our current manufacturing procedures, the reproduction has no tool stamping marks and the edges of the part are cleaner than the original. Making this a concourse level part.