Watts RK 800M4-CK Check Repair Kit 1 in. (0887704P)

OEM replacement check repair kit for Watts pressure vacuum breakers. The RK 800M4-CK 1 (Watts part 0887704 / 0887704P) restores the check valve function on 1-inch 800M4 and LF800M4 series PVBs to protect potable water from back‑siphonage. This factory kit includes the exact components needed to repair the internal check assembly and return the unit to reliable service life.

• Kit contents: check disc assembly (disc and disc holder), bonnet O‑ring, and check spring.
• Compatible models: Designed for 1" 800M4 and LF800M4 series PVBs (fits models such as 800M4QT and LF800M4QT).
• Performance benefit: Restores positive check seating to prevent reverse flow and protect potable water systems.
• Serviceability: Factory parts ensure correct fit; no special tools are typically required for changing the check components when following Watts service instructions.
• Durability: Genuine Watts parts are manufactured to the original specification for long service life and reliable sealing.

Use this kit for routine maintenance or when inspection indicates worn check components. For safe, code-compliant repairs, follow the Watts repair manual for the 800M4 series or consult a qualified plumbing technician. Replace components at the first sign of wear to maintain backflow protection and avoid costly downstream contamination.