This mounting kit is required to install Dellorto 17.5mm carbs with slotted connectors on the original intake manifold and carbs with 24mm clamp lock (use without rubber). The kit includes: adapter, connector rubber, ring clamps and screws. For Kymco SF10 engines (horizontal cylinder), the Malossi mounting flange is additionally required, as it has a larger distance between the holes. The metal connector has an internal diameter of 17.5 mm. Dimensions of the rubber connector: Internal diameter: 23 mm External diameter: 40 mm Length: 38 mm