Extremely accurate-accurate within 3% of reading from 20% of full scale to full scale clockwise and counterclockwiseGuaranteed against defect in workmanship and materials for 1 year from the date of delivery providing that they have been used according to instructionsEngineered, precision bearing surfaces extend the calibrated life of the M line to as many as 60,000 cycles or more and ensure the most reliable performance possibleIn addition to flawless operation at release, calibration is completely external, unlike traditional mechanism that require disassembly and the replacement of blocks and shimsExclusive patented calibration mechanism-This patented mechanism allows for calibration in both the clockwise and counter-clockwise directions, plus with regard to spring rate, without the disassembly of the wrenchExclusive patented roller-release - This patented feature removes over 95% of the friction inherent in other click wrenches thereby extending life and providing for more reliable operationAll M series meets or exceeds all applicable requirements of: ANSI / ASME B107.14M, GGG-W-00686C, BS6073: 1988, ISO6789This protects against contamination of the working mechanism, and make calibration quick and easy
