Water cooled engine carb carburettor fit for 37cc Chinese water cooled Mini Motos， it is also used to modify 2 stroke 47cc/49cc air cooled engine mini moto.Inner Diameter of Outlet: 19mmOuter Diameter of Air Filter Connection Point : 58MMSet for Chinese made two strokes'47cc 49cc 50cc 60cc 66cc 80ccpoket bike/Mini Bike/Mini ATVPackage Included: 1 x Carb + 1 x Intake + 1 x Gasekt + 1 x Air Filter