KDT81912 Features: -Surface Drive Plus provides stronger grip on fasteners. -Reduces fastener rounding. -Delivers up to 25% more torque. -Non-ratcheting offset box end. Use: -Combination Wrench/Torque Wrench. Size: -12mm/13mm. Quantity: -Set. Measurement Type: -Metric. Dimensions: Overall Product Weight: -4.3 Pounds.