Tile Bridge for Ceiling Speakers. The SA-TB is a tile bridge designed to mount 8 inch loud speaker and bridges both 2 ft x 2 ft and 2 ft x 4 ft ceiling tiles. It is compatible with the Viking models SA-1S, 30AE, and 35AE speakers. The SA-TB tile bridge is constructed of 24 gauge cold rolled steel with an electro galvanized rust-resistant finish. Applications Installations which require ceiling speaker enclosures When light duty ceiling tiles need help supporting a ceiling speaker Features Fits standard 8 inch ceiling speakers Bridges both 2 ft x 2 ft and 2 ft x 4 ft ceiling tiles Threaded mounting holes for easy installation 24 gauge galvanized steel.