Penn-Plax Check-Valve / Air Filter is perfect for use with your aquarium air pumps & accessories. The air filter provides clean air to your pump removing small particulate matter that may clog air stones or other air devices. The check valve engages whenever your air pump is off or in the event of a power outage stopping water from siphoning back into your air pump and preventing possible water damage. The check valve also makes adding and removing devices safer and can save you the cost of replacing an expensive device or changing contaminated air lines.

• Provides clean filtered air to your aquarium
• Keeps your air pump safe from water damage
• Reduces particulate matter that can clog air stones & other devices
• Prevents siphoning due to a power failure or when disconnecting other accessories