USG Shower Tray Disk is an ABS shower tray disk that comes with a removable subfloor cut out template. The USG Shower Tray Disk is also designed to hold the bonding flange drain in a solid position. The shower tray disk has clock like marking to allow an easier way for positioning your drain during installation. This component is essential in the USG Durock Shower Tray and Drain installation. Simply lay the Shower Disk in the tray opening, position the template, trace and cut.