Cartridge 20in Empty for 4.5x20 Housing Media Cartridge holds granular media, typically DI Resin, The cartridge is for the 4 x 20in Housing. Blue Caps with particulate filters to keep the media in the cartridge. Cartridge is installed in the Housing per the Directional Arrow and the Hole on the top with Gasket. Plastic End Caps and Housing Tubes offer long life.

Housing for 4.5x20 Filter Cartridge Insert - Typically DI Resin, The 1 inch port allows a greater volume of liquid to pass through the cap and the the built-in pressure release button in the cap allows for easier loosening the clear sump when it's time to replace the filter. This 4.5x20 Filter Housing accommodates a wide variety of 20-inch x 4.5-inch filters of your choice. When use for Water Purification (vs filtering) this 4 x 20in Size is preferred for holding DI Resin inside of an internal 20in Cartridge (not included).

Sediment Filter 4.5in x 20in Spun Poly ProTool bonded Sediment filter. 5 Micron Rating, Constructed of thermally bonded 100% Pure polypropylene microfibers. Contains no binders, agents, solvents, antistatic materials or wetting agents. its a universal water filter replacement fits any standard 4.5 x 20 inch housing for commercial or whole house system. Capacity 125,000 to 140,000 gallons, replace at least annually. It has sediment filter for sand, dirt, silt, rust, and scale particles reduction 5 Micron.