Fuel pump adapter includes a heat treated steel driveshaft that couples the fuel pump to the fuel pump drive mount. Driveshaft is .375" male hex on one end and .375" female hex on the other end. Shaft measures 2.00" end to end for bolt on applications, 2.375" end to end for quick clamp applications, male hex is .450" long, female hex is .550" deep and shaft diameter is .625".