Having a large intake manifold makes little difference without the correct reed block. This low-cost racing reed block makes for a clear path and greater flow rate. The rubber vulcanized glass fibre membranes seal far better than standard items. The greater flexibility means greater responsiveness. Even when they fail, they cause significantly less damage than the original metal parts. Fits on all vehicles with air-and water-cooled Piaggio 2-stroke engines. Replacement membranes can be ordered separately.