Waterway 550-0701 Pro Clean Plus Lock Ring

Engineered as an OEM replacement, the Waterway 550-0701 is a lock ring assembly designed for the Waterway Pro Clean Plus cartridge filter series. The lock ring is the component responsible for securing the filter tank lid to the base under operating water pressure, forming the watertight seal that keeps the filter pressurized and functioning properly during the entire filtration cycle. When the lock ring becomes cracked, warped, or broken, it ranks among the most common causes of lid leaks and pressure loss on Pro Clean Plus filters, which makes replacement an essential maintenance step rather than an optional one. An important fitment note applies: the 550-0701 is the new-style lock ring and is compatible only with Pro Clean Plus filter bases manufactured from 2015 onward, because a separate lock ring is offered for pre-2015 bases. The 550-0701 is also cross-referenced as Leslie's and Jacuzzi part number 370245 across various distributor catalogs.

Highlights

• Factory-Spec Waterway OEM Build: Manufactured by Waterway Plastics to exact OEM specifications, the 550-0701 lock ring delivers the dimensional accuracy and clamping force needed for a secure, properly sealed fit on Pro Clean Plus cartridge filter bases produced from 2015 forward.
• 2015+ Base Fitment Required: Because the 550-0701 is the new-style ring, it fits only Pro Clean Plus filter bases manufactured in 2015 or later, and Waterway uses a different lock ring on pre-2015 bases, so confirming the filter's manufacturing date before ordering is essential to avoid a non-fit situation.
• Brings Back Watertight Sealing: Under operating pressure, the lock ring is what holds the filter lid firmly against the tank body to maintain the watertight seal, and replacing a damaged ring with the correct 550-0701 OEM unit restores the proper seal and addresses one of the most frequent causes of pressure loss and lid leakage on the Pro Clean Plus series.
• Built-In Yellow Latches: The assembly includes integrated yellow latches that are not offered separately, so ordering the 550-0701 provides the complete lock ring and latch unit required to fully restore the lid-to-base locking and sealing system on compatible filter models without needing to source additional parts.
• Matches Leslie's/Jacuzzi 370245: The 550-0701 is verified as a direct cross-reference for Leslie's and Jacuzzi part number 370245, which helps customers confirm fitment whether they're searching by Waterway, Leslie's, or Jacuzzi part numbers across distributor and service references.