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Designed for fast and efficient installation, the Flash Shower Rough-In Valve provides flexibility for every situation. The Rough-In Valve features a flat back and compact body to ensure a secure and simplified install process that can accommodate smaller spaces. A flush plug is included, which allows both Hot & Cold to be flushed simultaneously for quicker installation and less downtime. Stainless steel fixation ring, with sure-grip flats, keeps flush plug and cartridge in place without screws.