MC^MP 30mm Carb Carburetor of for GY6 250cc CF250cc Water-cooled ATV Go Kart Moped Scooter 4 Wheeler Quad Bikes 30mm Carburetor fits for GY6 250cc Engine,CF250cc Water-Cooled Engine The inside diameter of carburetor: 30mm. The outside diameter connected with air filter: 50mm The material: total aluminium .