Penn Plax Air Tech 3-Way Visual Air Regulating Valve (1.75"L X 2.25"W X 3.5"H)

The most precise aquarium air control valve ever! Simply turn the air control knobs and the accurate visual gauges indicate flow to your decorations and airstones.Safe, anti-siphon feature protects your valuable air pumps.Extra input/output allows connection of additional pump or valve.Adjustable universal hanger is designed to fit securely on all tank frames.Convenient flip cover protects against mineral buildup and helps maintain a clean appearance.All plastic construction makes this valve suitable for both fresh and saltwater applications.