Note Use the higher values for head bolts with longer thread engagement and the lesser values for back- plate,valve covet etc. These value consider all threads in good condition. Proper care and maintenance. 1 the torque is precision instrument and should be handle and store with care. 2.When the wrench is not in use, keep it set at the lowest setting. 3 other than periodic calibration checks and adjustment, no maintenance is require. CALIBRATION TO 32B14-3-1-101 TECHNICAL MANUAL OPERATION AND SERVICE INSTRUCTIONS TORQUE INDICATING DEVICES 10 MAY 1993 CHANGE 14-28 OCTOBER 2011