This Chevy BBC Remote Oil Cooler Sandwich Adapter is used up to Mark IV. It provides an in and out port for installing an oil cooler. It mounts between the oil filter and block, replacing the stock bypass and bolting into the mounting holes left after the bypass is removed. The filter is lowered only 1-1/2". Oil ports are 1/2" N.P.T. Comes complete with O-Rings and hardware.