Miniature washing machine box

Abstract From the Canadian patent

A washing machine outlet box of the type capable of fitting within a wall and attaching to wall studs within this wall is improved by incorporating during the manufacture of said washing machine outlet box a disc as an integral part of the bottom wall, with the disc located over the future drain opening. The disc is attached to the bottom wall by a breakable or severable ring. After installation of the washing machine outlet box to an appropriate drain pipe, the disc serves as a plug for pressure testing of the drain pipe and further serves as a dam to prevent introduction of foreign material into the drain pipe during construction stages of the wall and the like. Upon completion of …