Slide-Out Splice Shelves Plugsters Slide-Out FDU’s are accessible via a base panel that slides out of the side of the unit.FRM-3RU-SS 4 trays, 5.25″H x 17″W x 14.0″D Rack Mount 3RU in height slide out master splice tray support panel. FRM-4RU-SS 8 trays, 7.0″H x 17″W x 14.0″D Rack Mount 4RU in height slide out master splice tray support panel. FRM-8RU-SS 16 panels, 14.88″H x 17″W x 14.0″D Rack Mount 8.5RU in height slide out master splice tray support panel.