Zodiac Jandy Pro Series JS60-SM 24" Outlet Fitting (R0520300) outdoor Check valves are useful because

Check valves are useful because they help maintain one-way flow and reduce the chance of unwanted reverse movement within the line

When a check valve becomes unreliable or difficult to service

Helps restore dependable water-heating performance

Confirm the equipment model and part number before installation

and this Maytronics Dolphin Wave version uses the 9995721 reference

Zodiac Jandy Pro Series JS60-SM 24" Outlet Fitting (R0520300) outdoor Check valves are useful becauseThe JS60 SM 24 inch outlet fitting is a replacement component used in compatible Jandy systems where the outlet path must match the original equipment geometry. A damaged or incorrectly substituted outlet fitting can restrict flow, create leaks, or complicate service around the tank or equipment connection. This part helps restore the designed flow route and connection point without replacing the entire assembly. Confirm R0520300 against the model