These new professional torque wrenches have been re-engineered to be even more accurate, durable and easy to use. The square drive features a finger grip on the top ('mushroom' head) that assists with running down the nut until resistance is met. Calibration certificate to ISO 9000:2000. Factory calibrated to ±3%. Ergonomic new handle with a high proportion of soft-feel, high grip material. Handle material and lens resist all chemicals in common automotive, industrial and aviation use. Secure push/pull locking mechanism is quick and intuitive to use and prevents accidental adjustment. Large scale window and long scale length for great visibility and accurate setting. Unique on a torque wrench, the Timestrip® gives a visual indication that the wrench is due for re-calibration.