... calibration key not let go, about 3 seconds after shows "-CAL-" immediate let go, later, shows ... 01 or 0.001, calibration over. If after weighing or not accurate calibration, then the process ... calibration key not let go, about 3 seconds after shows "-CAL-" immediate let go, later, shows ... over.Note:1, electronic scale is a precision instrument, before use, please reference level adjust its level ...