Mega jet kit for Honda clone, GX160, GX200, Predator 212cc, GX340, GX390, Predator 420cc, and other engines. Includes (1) each of the following jets: .034, .035, .036, .037, .038, .039, .040, .041, .042. Stock jets on GX200s are .028. Stock jets on GX390s are .036-.038. Use a larger opening jet if you're running lean and a smaller one if you're running rich.