Nylon/aluminum. Standard Pump fits quart oil bottles. Flexible hose gets to hard to reach locations. Threaded (3/8″-16) fitting fits Mercruiser, OMC, Evinrude, Johnson, Honda (70hp & up), Volvo, Force, Mercury (US origin models) and Gamefisher lower units. Includes Yamaha adapter (8mm-1.25) fitting for Mercury (Japanese origin models), Yamaha, Nissan, Tohatsu, Honda