The FlushLine replacement cartridge for Sloan Flushmate is easy to install and offers an economical solution to repairing your Sloan brand toilet. This cartridge is designed to easily replace your Sloan Flushmate series 500 model toilet. The FlushLine cartridge is made in the USA with durable materials for the rigors of everyday use. This cartridge replaces Sloan Flushmate #C-100500-K and Gerber # 99-403. Fits Sloan Tank System Series: 500, 501, 501A, 501B, 503 & 504. Includes: Duckbill Replacement Valve, Filter Screen Disc, and Instructions