Pressure‑Assist 1.6 GPF Toilet Tank Replacement System for One-Piece Toilets, M-102540-F3A, 503 Series

This 1.6‑gallon pressure‑assist tank system is engineered for reliable performance in two‑piece pressure‑assist toilets, offering powerful flushing action and consistent flow. It is designed specifically for systems originally equipped with Flushmate III 503‑series technology, ensuring compatibility and dependable operation. Built to fit a wide range of OEM one‑piece pressure‑assist toilet tanks, this replacement system delivers strong drain carry and reduces the need for repeat flushing.

It uses pressure rather than gravity, producing a vigorous flush that meets performance expectations in both residential and commercial environments. The system includes key components such as the vessel (1.6 GPF), shank lock nut, and essential gaskets for tank‑to‑bowl integration—providing a complete solution for maintenance or replacement needs.

• Right-hand, left-hand, push button handle location
• Maintains consistent flush volume throughout long‑term usage
• Compatible only with 12‑inch rough‑in tanks for proper installation
• Helps reduce double flushing through high‑flow pressure‑assist operation
• Designed as a full replacement system for existing Flushmate M‑101526‑F3 setups
• Fits OEM 503‑series systems except Kohler K‑4404 and Gerber 28‑385 tank models
• Designed for use with two‑piece pressure‑assist toilet tanks for dependable operation
• Suitable for high‑demand environments such as hotels, schools, and commercial restrooms
• Pressure‑assist technology delivers stronger flushing performance compared to gravity systems
• Provides a 1.6‑gallon pressure‑assist flush system compatible with Flushmate III 503‑series toilets
• Includes all installation components: system vessel (M-102540-F3A), brass washer (E-103021-1), rubber washer (E-204289), shank locknut (B-103021), 5/16-18 brass hex nut (E-104021), gasket, bolt plate (E-406288)
• Fits Porcelain Brands: American Standard, KooHoo, Laufen, Niagara, Orion, Peerless, St. Thomas Creations, Universal Rundle, Vitromex, Vortens/Lamosa