This is a Direct replacement Air Pump for the Aquaclipse ZO-400 & 400-25. Runs on .28 amp and uses 1/2 the electrical energy as your current pump! Powerful, 8 psi twin bellow still provides a great pattern of air bubbles in the tank. Lasts 300% longer than the original crankshaft S40-BA33F. Pumps with fewer moving parts!