These are replacement CDI packs to upgrade Your ignition for more power and top end speed.They change the timing curve and eliminate the rev limiter.They will work on the GY6 engines from 50cc to 150cc and others.They are A/C powered. You can tell by the wire harness.The AIR CONDITIONING packs have four wires in the big plug and two in the small plug for a total of six wires.The DC packs have four wires in the big plug and only one in the small plug for a total of five wires.Many brands of scooters have this type engine. It is four cycle over head cam.This is the cheapest and easiest upgrade for this type engine.This is an upgrade only. It isn't a repair for other problems.If Your scooter is running good now, This will make it run better.Does not make it a rocket, Just makes it have some more power and better top end.( month thru Sat 2