Fuel cap used through tank manufacturers in combination with fillingneck in your choosen material. Could also be used to replace the original one in case of lost. Fillingneck are availible in aluminium, stainless steel and steel. The filler caps are availible with and without ventilation. Ventilation is needed or recommended in most situations. It's important to check your needs before ordering a cap. This cap is with lock and is vented.