1/2" Dr. Extensions, 1/2 in (female square); 1/2 in (male square) drive, 1 1/2"Designed for superior performance in a variety of lengths for hard-to-reach applicationsForged and machined for best fit and unyielding strengthPrecision heat-treated and tempered for optimal hardness, ductility and durabilityEasy to read stamp pattern in order to quickly