LCD display : 5 digit large screen LCD display, with word height of 18 mm Unit : rpm Range : 2,5 - 99.999 rpm Resolution ratio : 0,1 rpm (2,5~999,9 rpm) ... 1 rpm (1.000~99.999 rpm ) Basic precision : +/- (0,1%n+5d)rpm ; (2,5~999,9 rpm) +/- (1%n+5d)rpm ; (1.000~99.999 rpm) Laser power : CLASS II 2-5mW Sampling ratio : Once/second Measurement distance : 50~500 mm Time base : Quartz crystal Automatic shutdown : The instrument will shut down after 60 seconds without any pressing Operation environment : 0~50 celcius Storage environment : -10~80 celcius Power supply : 2x1.5 Volt AAA Battery Dimension : 55.7x29.9x127 mm Weight : 106 Gram