The Marina Ultra 3-way air control valve allows you to run up to 3 air-driven products at once. Each valve has a flow adjuster which enables you to regulate air output to each devise. The valve is leak-proof and suitable for fresh or saltwater aquariums. The valve can easily be hung on all standard aquariums. Other Marina Ultra air control valves available: -A1178 Marina Ultra 2-way air control valve -A1180 Marina Ultra 4-way air control valve -A1181 Marina Ultra 5-way air control valve