Exact Fit for American Standard 077171-0070A Designed to replace the original American Standard pressure balancing unit. Compatible with R111 / R121 series tub and shower valves including models 1321, 1325, 1351, 1354, and 1355. Please verify your valve model before ordering. Maintains Stable Water Temperature Automatically balances hot and cold water pressure to help maintain consistent shower temperature, reducing sudden temperature changes and improving overall shower comfort. Easy DIY Replacement – No Special Tools Required Simply shut off the water supply, remove the old pressure balancing unit, and install the replacement. Designed for direct replacement into existing American Standard valve bodies. Durable Construction with Reliable Sealing Made from high-quality ABS housing with brass components and integrated sealing rings to ensure smooth operation, reliable pressure balance, and leak-free performance. Ideal Solution for Common Shower Issues A practical replacement part for addressing inconsistent water temperature or pressure imbalance. If you are unsure about compatibility, remove the trim and compare the original part before purchase. Compatibility: Designed to fit American Standard Pressure Balance Shower Valve models R111 and R121, including 1321, 1325, 1351, 1354, and 1355 series. Direct replacement for 077171-0070A / M961622-0070A cartridges. Pressure Balancing Function: Maintains stable water temperature by automatically adjusting pressure differences between hot and cold supplies, effectively preventing scalding. Reliable Structure: Integrated check valves eliminate crossflow, while precision-molded ABS housing resists corrosion and mineral build-up for long-lasting performance. Easy Installation: Simply remove the old valve assembly and install the ALITZ cartridge with your existing shower valve body – no special tools required. High Quality Materials: Made of premium ABS and brass components with double O-rings, ensuring a leak-free seal and smooth operation over time.