The CPAP Store USA Cartridge Filter & Check Valve for SoClean 2 Cleaner and Sanitizer. When installed the SoClean’s Cartridge Filter converts activated oxygen back to regular oxygen as it leaves the SoClean device. The Check Valve prevents water backflow from your CPAP humidifier into the SoClean 2 device or CPAP electronics. These are aftermarket filters.
Comes in a Pack of 2, 4 or 6