Gotobuy - Marine Engine Boat Primer Fuel Hose Low Permeation Bulb Assembly Hand Pump Primer Bulb Ball 3/8" Fitting with Aluminum Head Material: Rubber Body and Aluminium Head Aluminum head is more longer using life than plastic head. Rubber Body is good oil-proof and good air-proof. Length (overall): 150 mm Length (without hose connections): 116 mm