{"id":15441076650135,"title":"Replacement for Kohler GP876851 Mixer Cap and Pressure Balance Shower Kit","handle":"replacement-for-kohler-gp876851-mixer-cap-and-pressure-balance-shower-kit","description":"\u003ch3\u003eReplacement for Kohler GP876851 Mixer Cap and Pressure Balance Shower Kit\u003c\/h3\u003e\n\u003cp id=\"b\"\u003e\u003c\/p\u003e \n\n\u003ch3\u003eProduct Features\u003c\/h3\u003e\n \u003cul class=\"a\"\u003e\n \u003cli\u003eFITS KOHLER K-304 VALVES: Mixer cap and pressure balancing unit kit for Kohler single-handle tub and shower valves on the K-304 and K-11748 platforms, and compatible with Sterling valves that take the A2758 cartridge. Functions as a replacement for the Kohler GP876851 kit, and for the GP800820 or GP500520 cartridge and GP77759 mixer cap when those are bought separately. Restores stable hot and cold control on valves with a round splined brass stem.\u003c\/li\u003e\n \u003cli\u003eSTOPS DRIPS AND SPIKES: Fixes the shower that drips at the head or tub spout after shutoff, weeps around the handle base, drifts lukewarm partway through a shower, or spikes hot when a toilet flushes or a washer fills. Replacing the cartridge and the cap together restores positive shutoff and steady temperature without opening the wall or replacing the brass valve body.\u003c\/li\u003e\n \u003cli\u003eCAP, CARTRIDGE, HARDWARE: Every kit ships with the black mixer cap and its four-lobe mounting flange, the pressure balancing unit with brass splined stem and red limit stop ring, four O-rings, and two cap screws. Nothing else to buy for the repair. Engineered polymer body with brass stem and metal bolt bushings, 3-5\/8 inch assembled length, 36mm cartridge body diameter, EPDM seals.\u003c\/li\u003e\n \u003cli\u003eHOW TO IDENTIFY YOUR PART: Pull the trim and look for a black plastic cap retained by two side screws and a metal collar, with a brass splined stem and a red plastic limit stop ring on the cartridge underneath. The cap flange has four lobes with metal bushings at the bolt points, and the cartridge lifts straight out of the brass body once the cap is off. A valve matching that profile takes this kit.\u003c\/li\u003e\n \u003cli\u003eKOHLER PART NUMBERS: Serves as a replacement for the Kohler GP876851 and GP76851 mixer cap and pressure balancing unit kits, the GP800820 and GP500520 cartridge, and the GP77759 mixer cap. Also cross-references Sterling A2758 and the legacy Kohler service numbers 30086 and 42030 covering the same repair on K-304 and K-11748 valve platforms.\u003c\/li\u003e\n \u003cli\u003eAFTERMARKET CROSS-REFS: Cross-references Everbilt 49868, Kissler 46-0080, and Home Depot counter number RGP500520, which cover the pressure balancing unit portion of this repair. This kit ships the mixer cap, four O-rings, and two cap screws alongside the cartridge, so the complete cap and unit service is one part number and one box.\u003c\/li\u003e\n \u003cli\u003e20 TO 30 MINUTE INSTALL: Shut off the water, pull the handle and escutcheon, back out the two side screws, lift off the metal collar and the old cap, then draw the old pressure balancing unit straight out with pliers. Grease the small O-rings and seat the new unit level. Do not set it in at an angle and rotate it, that displaces the O-rings and creates a leak. Align the cap tab to the notch with the top at 12 o'clock, refit the collar, tighten both screws.\u003c\/li\u003e\n \u003cli\u003eFOURHOME QUALITY BUILD: Cap flange, bolt spacing, cartridge body diameter, stem spline, and O-ring seats are inspected against the Kohler GP876851 dimensional spec before packaging, so the unit seats in the brass body and the handle engages without modification. The parts that fail first on a used valve are the large cap O-ring, the two small inlet O-rings, and the limit stop ring, and all of them ship new in every kit.\u003c\/li\u003e\n \u003cli\u003eVERIFY BEFORE ORDERING: Confirm the valve is a Kohler K-304 or K-11748 platform, or a Sterling valve that takes the A2758 cartridge, and check the old part number against GP876851, GP76851, GP800820, GP500520, GP77759, or A2758. The old cap should have a round splined brass stem. Does not fit valves that use the GP800881 cartridge (K-8300, K-8304), the GP77886 or GP71969 square stem caps, 3\/4 inch valves, thermostatic valves, or diverter and volume control valves.\u003c\/li\u003e\n \u003c\/ul\u003e","published_at":"2026-10-25T14:40:15+11:00","created_at":"2026-10-24T22:19:34+11:00","vendor":"FOURHOME","type":"Cartridges","tags":["home_improvement_Oct2026"],"price":20900,"price_min":20900,"price_max":20900,"available":true,"price_varies":false,"compare_at_price":null,"compare_at_price_min":0,"compare_at_price_max":0,"compare_at_price_varies":false,"variants":[{"id":68128095633559,"title":"Default Title","option1":"Default Title","option2":null,"option3":null,"sku":"B0D9P166Z3","requires_shipping":true,"taxable":true,"featured_image":null,"available":true,"name":"Replacement for Kohler GP876851 Mixer Cap and Pressure Balance Shower Kit","public_title":null,"options":["Default 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for Kohler GP876851 Mixer Cap and Pressure Balance Shower Kit\u003c\/h3\u003e\n\u003cp id=\"b\"\u003e\u003c\/p\u003e \n\n\u003ch3\u003eProduct Features\u003c\/h3\u003e\n \u003cul class=\"a\"\u003e\n \u003cli\u003eFITS KOHLER K-304 VALVES: Mixer cap and pressure balancing unit kit for Kohler single-handle tub and shower valves on the K-304 and K-11748 platforms, and compatible with Sterling valves that take the A2758 cartridge. Functions as a replacement for the Kohler GP876851 kit, and for the GP800820 or GP500520 cartridge and GP77759 mixer cap when those are bought separately. Restores stable hot and cold control on valves with a round splined brass stem.\u003c\/li\u003e\n \u003cli\u003eSTOPS DRIPS AND SPIKES: Fixes the shower that drips at the head or tub spout after shutoff, weeps around the handle base, drifts lukewarm partway through a shower, or spikes hot when a toilet flushes or a washer fills. Replacing the cartridge and the cap together restores positive shutoff and steady temperature without opening the wall or replacing the brass valve body.\u003c\/li\u003e\n \u003cli\u003eCAP, CARTRIDGE, HARDWARE: Every kit ships with the black mixer cap and its four-lobe mounting flange, the pressure balancing unit with brass splined stem and red limit stop ring, four O-rings, and two cap screws. Nothing else to buy for the repair. Engineered polymer body with brass stem and metal bolt bushings, 3-5\/8 inch assembled length, 36mm cartridge body diameter, EPDM seals.\u003c\/li\u003e\n \u003cli\u003eHOW TO IDENTIFY YOUR PART: Pull the trim and look for a black plastic cap retained by two side screws and a metal collar, with a brass splined stem and a red plastic limit stop ring on the cartridge underneath. The cap flange has four lobes with metal bushings at the bolt points, and the cartridge lifts straight out of the brass body once the cap is off. A valve matching that profile takes this kit.\u003c\/li\u003e\n \u003cli\u003eKOHLER PART NUMBERS: Serves as a replacement for the Kohler GP876851 and GP76851 mixer cap and pressure balancing unit kits, the GP800820 and GP500520 cartridge, and the GP77759 mixer cap. Also cross-references Sterling A2758 and the legacy Kohler service numbers 30086 and 42030 covering the same repair on K-304 and K-11748 valve platforms.\u003c\/li\u003e\n \u003cli\u003eAFTERMARKET CROSS-REFS: Cross-references Everbilt 49868, Kissler 46-0080, and Home Depot counter number RGP500520, which cover the pressure balancing unit portion of this repair. This kit ships the mixer cap, four O-rings, and two cap screws alongside the cartridge, so the complete cap and unit service is one part number and one box.\u003c\/li\u003e\n \u003cli\u003e20 TO 30 MINUTE INSTALL: Shut off the water, pull the handle and escutcheon, back out the two side screws, lift off the metal collar and the old cap, then draw the old pressure balancing unit straight out with pliers. Grease the small O-rings and seat the new unit level. Do not set it in at an angle and rotate it, that displaces the O-rings and creates a leak. Align the cap tab to the notch with the top at 12 o'clock, refit the collar, tighten both screws.\u003c\/li\u003e\n \u003cli\u003eFOURHOME QUALITY BUILD: Cap flange, bolt spacing, cartridge body diameter, stem spline, and O-ring seats are inspected against the Kohler GP876851 dimensional spec before packaging, so the unit seats in the brass body and the handle engages without modification. The parts that fail first on a used valve are the large cap O-ring, the two small inlet O-rings, and the limit stop ring, and all of them ship new in every kit.\u003c\/li\u003e\n \u003cli\u003eVERIFY BEFORE ORDERING: Confirm the valve is a Kohler K-304 or K-11748 platform, or a Sterling valve that takes the A2758 cartridge, and check the old part number against GP876851, GP76851, GP800820, GP500520, GP77759, or A2758. The old cap should have a round splined brass stem. Does not fit valves that use the GP800881 cartridge (K-8300, K-8304), the GP77886 or GP71969 square stem caps, 3\/4 inch valves, thermostatic valves, or diverter and volume control valves.\u003c\/li\u003e\n \u003c\/ul\u003e"}