Natural Chemistry Pool Perfect Max w/ PHOSfree - 3 liter confer-plastics It has an inside diameter

It has an inside diameter of 5-3/8"

The Hayward SPX0715X32 Side Mount Multiport Valve has 6 available positions: Filter

Manufacturer Part # CX225RE

Manufacturer Part # 330024BR4

Salt Cell (W3SAS-CELL) is sold separately

Natural Chemistry Pool Perfect Max w/ PHOSfree - 3 liter confer-plastics It has an inside diameterTake pool maintenance to the next level! Pool Perfect Max is Natural Chemistrys premier maintenance formulation. Added weekly, this product reduces the amount of time and effort you have to spend on pool care. Its key benefits include: working as a continuous filter cleaner, removing maintenance levels of problem causing phosphates, reducing scrubbing of scum lines and waterline ring polishing water to sparkle like never before. Simply add one capful