This teng tools industrial wrench is made of chrome vanadium steel for increased strength and durability it exceeds international standards iso 6787 1976 asme b1078m 1996 bs6333 1995 din 3117 1988 and jis b4604 1976 graduated markings on the jaw allow the size of the fastening to be accurately measured and the wrench to be set at the right size the 15 degree jaw angle allows the wrench to be used in narrow spaces as only 30 degrees turning is needed the wider jaw opening increases the range of b