These are new mounting pads for the small block and big block Chevrolet. This is the side bolt style mount used on our 1947 to 1959 V8 engine conversion or 1963 to 1972 V8 engine conversion. For 1963 to 1972 trucks with original frame mounts that use the center bolt style mount. Use part# bbmm2ur. Anyone with a high horsepower application needs these. We have also had these designed with an interlocking feature to still hold the engine in the case of a cushion failure. These are in black urethane. Sold individually. 2 pieces required per vehicle.