IZTOSS LCD Display Digital Tachometer RPM Tacho Gauge Hour Meter For Motorcycle/Boat Engines Functions: Digital Tachometer Hour Meter Display: Large 3/8 inch LCD display Product Dimensions(L x W x H): 73 x 47 x 20mm Great for Cart Engines operating in the 25,000 + RPM range With wrap black wire around sparkplug wire, can work on all spark ignition engines by selecting engine type using S1 and S2 buttons