For 125CC 150CC 200CC 250CC 300CC ATV Dirt Pit Go Kart Motorcycle Ignition Ignite System Unit 4 Pin DC CDI Box With DIP Switch 4 pin dual plug CDI fits many 4-stroke models of ATVs, dirt bikes, go karts, scooters, and mopeds. Many size engines require this CDI, including 50cc to 110CC . Verify the number of pins and style of plug for best match of your CDI. Feature: High class quality and very durable 4-pin 4 prong Current mode DC CDI Fitment: For 50cc 70cc 90cc 110cc 125cc Scooter ATV Dirt Bike Go Kart DC CDI DIP switch operation instructions: All DIP switches are turned up, which is the normal ignition mode of the igniter. When all DIP switches are down, the igniter is in the speed limit mode of 4000RPM. DIP switches 1, 2, 3 up and 4 down indicate that the igniter is in infinite speed mode. DIP switches 1 up, 2, 3, and 4 down indicate that the igniter is in the speed limit mode of 6000RPM. DIP switches 1, 2 up, 3, 4 down indicate that the igniter is in the speed limit mode of 8000RPM. DIP switches 2 up, 1, 3, and 4 down indicate that the igniter is in the 7000RPM speed limit mode. DIP switch 3 up and 1, 2, 4 down indicate that the igniter is in the speed limit mode of 9000RPM. When DIP switches 1, 2, and 3 are down, the igniter is in the speed limit mode of 4000RPM. At this point, the 4 switch can be switched up or down, indicating that the igniter is in a curve changing mode, that is, the advance and delay angle changes. AC or DC? Most machines (especially the newer they are) are AC. DC CDI boxes are larger than AC CDI boxes. The easiest way to tell if your machine is AC or DC is to turn on the headlights with the machine turned off and the ignition in the ''ON'' position. If the headlight comes on, it is a DC machine; if it does not, it is an AC machine. Package Includes: 1 piece CDI BOX (As shown in option picture)