3 PCS Marine Boat Black Rubber Jumbo Primer Bulb Hose for Outboard Fuel Tanks This is a set of 3 black rubber jumbo primer bulbs for outboard fuel tanks. The primer bulb and hose allow greater fuel flow to maximize performance. Compounded to accommodate today's alcohol-enriched gasoline blends. Item: P40061X3 It fits with 3/8" hose.