Description This item is a digital tachometer gauge and hall proximity switch set. Both of the tools are made of quality plastic for wear resistance purpose. The tachometer measuring range is up to 9999RPM and it will show "1" or "-1" when the data is beyond its measuring range. Feature - This PRM meter works with many kinds of devices - With digital screeen, nice knowing actual rpms rather than relying on guesstimates. - The hall sensor will light up to let you know it is getting power. - It shows the measuring data accurately, and they are easy to install. - The meter is designed to snap into a rectangular opening for flush mount. Specification - Color: Mainly Black - Material: Plastic - Tachometer Size: 79x41x25cn/31x16x9.8inch - Hall Proximity Switch Size: 40x22x12mm/1.6x0.9x0.5inch - Power requirement: DC 8-24V 30mA - Measure range : 10-9999RPM. - Refresh frequency: 0.2-0.5S@120-1200RPM;0.25-0.06S@2400-9999RPM. - Measure accuracy: RPM<5000,±2;RPM>5000,±3. - Hall proximity model: CF5135C-Z - Detection range: 10mm - Detected objects: Magnet - Response frequency: 9999Hz999.9hz99.99khz - Sensor wiring:brown means power+; blue means power-; black means signal. - Operating temperature: 0 to 50°C.Packing list: 1 x Tachometer 1 x Hall Proximity Sensor