Replacement for Kohler GP500520 GP800820 GP800881 | Pressure Balance Shower Cartridge for Kohler K-304, K-11748 & Sterling Rite-Temp Shower Valves | Anti-Scald Hot & Cold Control | 3-5/8 Inch — Open-Box, 21% Off

REPLACEMENT FOR KOHLER RITE-TEMP CARTRIDGE: Replacement for Kohler OEM service parts GP500520, GP800820, and GP800881, restoring proper hot and cold water control in leaking or worn Kohler and Sterling Rite-Temp single-handle shower valves. Compatible with K-304 and K-11748 valve platforms across Kohler trim families including Devonshire, Forte, Coralais, Bancroft, and Memoirs.

STOPS LEAKING, DRIPPING, AND TEMPERATURE SWINGS: A worn pressure balancing unit causes constant dripping at the showerhead or tub spout, water weeping past the handle base, temperature creep during use, and the sudden hot-cold spike when a toilet flushes or another fixture runs. Installing a fresh cartridge with new O-rings restores positive shutoff and stable temperature without replacing the valve body or opening the wall.

ENGINEERED POLYMER WITH BRASS SPLINED STEM: Built from corrosion-resistant engineered polymer with a brass splined stem, stainless steel mounting plate, and four pre-installed EPDM O-rings. Correct 36mm cartridge body diameter, 3-5/8 inch overall length, and 4-bolt mounting interface for a leak-free seal and secure handle engagement in Kohler and Sterling Rite-Temp valve bodies.

ANTI-SCALD PRESSURE BALANCE PROTECTION: This Rite-Temp pressure balance cartridge maintains a stable shower temperature within plus or minus 3 degrees Fahrenheit even when another fixture in the home runs. The integrated pressure balancing unit prevents scalding when a toilet flushes and prevents thermal shock when cold water suddenly cuts off, meeting modern code requirements for residential shower safety.

CROSS-REFERENCES THE FULL RITE-TEMP SERVICE FAMILY: Cross-references Kohler GP500520, GP800820, GP800881, the cartridge portion of the GP76851 mixer cap and pressure balancing unit kit, Everbilt 49868, and Sterling A2758. One cartridge covers the standard service numbers for the Kohler shower mixer valve across residential Rite-Temp installations.

CONSIDER REPLACING THE MIXER CAP AT THE SAME TIME: The four-bolt brass mixer cap that holds the Rite-Temp cartridge inside the valve body is a separate Kohler service part. Common Kohler mixer caps are GP77759, GP77886, and GP71969, also serviced as the GP76851 cap and cartridge kit. If the cap shows cracks at the bolt bosses, scale buildup on the sealing face, or stripped threads, replace it during the same repair. This listing is the cartridge only.

FOR PROPERTY MAINTENANCE AND TRADE BUYERS: A standard truck-stock cartridge for property managers, multifamily maintenance teams, hospitality operators, and plumbing contractors servicing Kohler and Sterling Rite-Temp showers at scale. Available to Amazon Business customers for multi-unit and recurring orders.

QUICK DIY SHOWER CARTRIDGE REPLACEMENT: Complete the repair in 20 to 30 minutes using basic hand tools. Shut off the water, remove the handle and trim, back out the four bolts on the brass mixer cap, pull the old cartridge straight out, lubricate the new O-rings with plumber's silicone grease, press the new cartridge into the valve body, and reassemble.

FOURHOME QUALITY AND LEAD-FREE COMPLIANCE: All metal components in contact with potable water meet the federal Reduction of Lead in Drinking Water Act standard for residential and commercial plumbing. Body diameter, stem spline, O-ring seats, and the 4-bolt mounting pattern are inspected against the Kohler GP500520 dimensional spec before packaging so the cartridge seats and seals without rework.

VERIFY COMPATIBILITY BEFORE ORDERING: Confirm your shower valve is a Kohler K-304 or K-11748 Rite-Temp platform or a Sterling Rite-Temp valve, matched against GP500520, GP800820, GP800881, or any cross-reference number listed. Not compatible with Kohler K-8304 valves, which require the K-8305 cartridge, or with older brass-body Kohler shower valves that pre-date the Rite-Temp platform.

When a Kohler or Sterling Rite-Temp single-handle shower drips at the showerhead or tub spout, weeps past the handle, drifts in temperature mid-shower, or spikes hot when a toilet flushes, the cause is a worn pressure balancing unit inside the valve. This is a replacement pressure balance shower cartridge for Kohler K-304 and K-11748 Rite-Temp valves and Sterling Rite-Temp valves, covering service part numbers GP500520, GP800820, and GP800881, and it restores anti-scald hot and cold control without replacing the valve body or opening the wall. The cartridge is built from corrosion-resistant engineered polymer with a brass splined stem, stainless steel mounting plate, and four pre-installed EPDM O-rings, with the correct 36mm body diameter and 3-5/8 inch overall length. The integrated pressure balancing unit holds shower temperature within plus or minus 3 degrees Fahrenheit when pressure shifts elsewhere in the home. The four-bolt mounting interface fits the existing Kohler mixer cap, including GP77759, GP77886, and GP71969 caps, also serviced together as the GP76851 mixer cap and pressure balancing unit kit. Cross-references include Everbilt 49868 and Sterling A2758. Compatible Kohler trim families include Devonshire, Forte, Coralais, Bancroft, and Memoirs. This is the cartridge only. The mixer cap is a separate service part, and if the cap shows cracks at the bolt bosses, scale on the sealing face, or stripped threads, replace it during the same repair to avoid creating a new leak around the fresh cartridge. Not compatible with Kohler K-8304 valves, which use the K-8305 cartridge, or with older brass-body Kohler shower valves that pre-date the Rite-Temp platform. Confirm the valve model before ordering. Installation takes 20 to 30 minutes with basic hand tools. Shut off the water, remove the handle and trim, back out the four bolts on the brass mixer cap, pull the old cartridge straight out, lubricate the new O-rings with plumber's silicone grease, press the new cartridge into the valve body, and reassemble. Test both hot and cold through the full handle sweep before closing up the trim. Every cartridge is inspected against the Kohler GP500520 dimensional spec before packaging: same body diameter, same stem spline, same mounting pattern, so it seats in the valve body and engages the handle without modification.