If you're rebuilding or repairing a small pit bike, ATV, or go-kart, this complete wiring harness kit has everything you need to get the electric start system working. It's designed for Chinese-made 49cc, 50cc, 70cc, 90cc, 110cc, and 125cc engines with upright electric start. The kit includes: a full wire harness loom, a CDI box, an ignition coil with lead, a cluster switch (with remote choke), a key switch with 2 waterproof keys, a spark plug, a voltage regulator/rectifier, and a solenoid relay. It also comes with an installation diagram to help you hook it all up. The parts are decent quality for the price and should be a direct replacement for many common models like Coolster, Tao Tao, and other generic quads or dirt bikes. Whether your old wiring is fried, you're doing an engine swap, or building a project bike from scratch, this kit saves you from buying each part separately. Make sure your engine type matches before ordering. A must-have for any small engine mechanic or hobbyist.