Hayward Swimclear/Pro-Grid Air Relief O-Ring [Qty-2] (DEX2420Z8A) presairtrol a small fitting like this

a small fitting like this can have a major effect on whether the final layout feels clean and properly matched

and part number 56WUA400-I

which can add an extra layer of operator awareness and control

Because many pool and spa parts look similar but differ by size

A shaft like this is useful because it helps the bypass mechanism move and function properly

Hayward Swimclear/Pro-Grid Air Relief O-Ring [Qty-2] (DEX2420Z8A) presairtrol a small fitting like thisThe Hayward air relief O ring set is designed for compatible SwimClear and Pro Grid filter applications where the air relief assembly needs dependable sealing. O rings like these are useful because they help maintain a cleaner seal at the air relief point, supporting more reliable filter serviceability and operation. This quantity two replacement is especially useful when the original O rings are flattened, brittle, cracked, or leaking. Replacing them