Thank you for choosing our tachometer. Please read the entire operationmanual thoroughly before you use this instrument for the first time. Theinformation contained herein will help you to achieve accurate andreproducible results and avoids misuse or damages.Safety PrecautionsDo not stare into laser beam nor aim it towards human eyes.Class 2 laser products are safe, but may irritate the eyes inrare cases of high sensitivity or after a longer exposure withthe laser beam.Direct (contact) rpm measuring should not exceed the speedof 25.000 rpm. Use non-contact measuring mode to avoiddamages.The extension shaft should not be used together with a measuring wheel,as it may become loose and cause damages.Direct (contact) speed measuring with the measuring wheel should beused for speeds below 1500m/min only. For higher speeds take specialmeasure to fix the wheel to the shaft, or use the non-contact measuringmode to avoid damages.Before Taking Into Operation (BatteryReplacement)Open battery cover – Use a coin to unscrew.Replace battery – Please check polarity!Close battery cover.