Flying Horse 2-Stroke/4-Stroke Motorized Bicycle Gas Cap &ndash; Gas Bike Fuel Tank Gas Cap Replacement This Gas Cap is great for gas tanks used with any 2-stroke or 4-stroke bicycle engine kit To install, press the gas cap down in to the gas tank, twist until the arms pop in to position, and you're ready to ride Note: This gas cap will not fit on to plastic gas tanks. This cap is made for aluminum tanks found in most Flying Horse, Mega Motors, RAW, Grubee, Power King, or any Chinese made engine kit