1. Duct Diameter: 13MM; Air Filter Diameter: 44MM; Mounting Hole Spacing: 38MM 2. Replacement for 43cc - 47cc 49cc 2-stroke engines mini moto, ATV, quad, scooter, go kart, moped, chopper, brush cutter, pocket bike, dirt bike, super bike, rocket bike, mini bike and other bikes, G-Scooter X1 X2 X6 X8 3. Replacement for TaoTao, Buyang, Coolsport, Lifan Kazuma, Sunl, , Redcat, Eagle etc and various unlisted makes/models 4. Mix a certain amount of gasoline with air to keep the engine running