The RTX 100 120 maintenance pump from A.R. North America has stainless steel convexed intake and discharge valves for high fluid dynamic efficiency along with a high-strength, one-piece, nonporous forged nickel-plated brass head and forged heat-treated steel crankshaft. It has a dual high-pressure sealing system with anti-extrusion ring support lubricated with low-pressure recirculating lubrication chambers for the low-pressure seals, plus tapered roller crankshaft bearings. It can be connected directly or through an elastic coupling to different engines. The pump body and lids are constructed of diecast aluminum. It has a closed side with oil level indicator and rear cover with drain plugs. Movement of the pistons is via the connecting rod and crank. The pump shaft is made of high-resistance pressed steel. The connecting rods are a zinc alloy or diecast aluminum with antifriction properties. It has ceramic pistons and a double-gasket sealing system and valve caps in both the intake and exhaust sides for better maintenance. 800/893-4235; www.arnorthamerica.com.