Interchangeable head with square interface; Torque accuracy of +/- 3% CW in the upper 80% of wrench capability delivers high performance; 9mm x 12mm adapter size; Scale markings are highly visible and easy to read; Knurled aluminum handle lets you grip comfortably, while clearly marked midpoint promotes additional accuracy; 100% steel construction offers lasting strength and durability; Meets or exceeds ASME B107.300 and exceeds ANSI specifications on load and cycle