Conversion Cover Plate with Universal Pipe Boss 1½" (1.1/2"). For use with TSG1, TSG50, TSG52 and TSG2 Shower Gullies for sheet flooring. Please Note: Used to seal off Gully or to convert to a drain connection to allow for installation of bath waste. By refitting the Cover Plate and Dip Tube the drain reverts to a trapped Gully