PRECISION - Ships pre-calibrated to +/- 4% accuracy and ready to use. Include calibration certificate with traceable serial number. DURABLE - Reinforced ratchet gear head constructed from hardened, heat treated Chrome Vanadium alloy steel. LONG-LASTING - Rust & corrosion protection with our unique and newly invented Electro-Black finish treatment. PERFORMANCE - Features an easy-to-read, highlighted yellow print dual-range scale. Identify the markings even in low-light conditions. COMFORTABLE - Comes with a reversible ratchet head that drives in both directions and measure torque in a clockwise direction.