NON CONTACT LASER TACHOMETER Specifications: measuring range:2.5-99999rpm resolution:0.1rpm, at 2.5~999.9rpm;1rpm, at 1000~99, 999 rpm accuracy:±0.02%+1digtal measuring distance:50~500mm sampling time:0.5s(above120rpm) operation temperature:0 to 50oc(32 to 122of) operation humidity:10 to 90%rh storage temperature: -10 to 60oc(14 to 140of) storage humidity:10 to 75%rh dimension:145*90*35mm weight:120g(included battery) Features: mini handheld gun type design automatic and manual measurement selectable data record and recall max/min/avg value record function record time interval setup function lcd with white backlight data hold function auto and mamual power off low battery indication