These are absolutely the best and last floats you will ever buy for your Linkert Carburetor. The RUBBER DUCKY floats have been tested in the modern fuels available today that contain ethanol and various additives. Neither will they ever shrink nor corrode. Tests have also shown them to be reliable in 112 Octane Leaded Race Gas. RUBBER DUCKY Floats feature the correct weight and size so they can be set at the factory level which means they maintain the stock responsiveness and operation of your carburetor.