Oatey 38550 Quadtro Washing Machine Outlet Plain Box, No Valves Oatey QUADTRO washing machine outlet boxes can be used in commercial or residential applications which require supply valves and waste drain recessed into the wall. Available water hammer arrestor option provides water pressure shock arrestors required for installation on supply lines to quick closing valves. Features: 2″ drain opening fits PVC or ABS Schedule 40 DWV pipe. – Easy to remove knockout, Patent Pending Hammer Valves. – Snap-on Faceplate Frame accommodates up to 1″ drywall. – Box made of high impact polystyrene. – Top or Bottom Valve Mount.4 support brackets included for mounting. – Box Dimensions: 8-3/4″W x 7-1/2″H x 3-5/8″D.Faceplate Dimensions: 11-3/4″W x 10-1/8″H.