BQLZR 8mm Black Rubber Fuel Transfer Vacuum Fuel Line Hand Primer Pump Bulb Type For Marine Boat Accessories Length (overall): 150 mm Frequently used as a hand pump in boats for fuel supply to the out-board engine. Hand bulb primer to suit petrol of comes with a one way valve installed to help quickly prime the fuel system. Dimension:150 x 42mm/5.91 x 1.65"(L x Dia) Interface Size: 8mm