ERGOTRON 97-101-003 Wall Plate, Not compatible with HD Arms, Compatible with LX Arms when attaching to the wall with steel studs, Fasteners for attaching to the wall not included, Aluminum This Ergotron Wall Mount Plate allows user to mount 400 series Flat Panel vertical mount arms, 400 series extender arms, 200/300 series vertical mounts and 100 series pivot direct mounts to a wall or other vertical surfaces.