GC Tek Media Agitator Replacement Spring Check Valves Tabs/Packs Independent laboratory testing confirms that

Independent laboratory testing confirms that the Ultima II filter is superior to three leading bead filter brands in setup

Built-in pressure relief valve protects the pump if airlines become kinked

To determine whether the left-side or right-side model is needed

Not available for purchase in California

Will not harm live plants or fish

GC Tek Media Agitator Replacement Spring Check Valves Tabs/Packs Independent laboratory testing confirms thatShips directly from the manufacturer, typically in 5 7 business days These replacement spring check valves are used as replacements for the double union check valves used on AquaBead filters. Available for older (retro) style and new (current) style media agitators.