Specification:-Power requirement:DC 8-15V or AC6-18V.-Measure range:99999 ~ 3.8RPM.-Error range: ± 0.5 ‰ - 1.5 ‰ rpm-Clear zero:Automatic .-Clear zero time:About 10s.-Refresh frequency: 0.2-0.5S(120-1200RPM)，0.25-0.06S(2400-9999RPM).-Response frequency:100HZ.-Measure indication:(RPM<5000，±2)，(RPM>5000，±3).-Sign:NPN 3 wires normally open.-Display:5 x 2.5cm red LED.-Tachometer size:78 x 42 x 13mm.-Panel cutout size:71 x 38mm.-Hall proximity model:NJK-5002C .-Detected objects: Magnet.-Detection range: 1mm-10mm.-Proximity output current: 20mA(For the sensor).-Operating temperature: -10 to 60°C.-Sensor wiring:brown(Power+)，blue(Power-)，black(signal).-Sensor size: 37 x 12 x 10mm.Pacage include:1 x Red LED tachometer1 x NPN hall proximity sensor