The BB-4L back box provides a recess-mounted steel enclosure for the Isys® TPS-4L Wall Mount Touch Screen. Designed for pre-construction applications, the BB-4L permits fastening to the stud of a framed wall prior to installation of sheet rock. An assortment of knockouts is provided to accommodate conduit fittings, and a blank cover plate is included to provide a temporary cover of the opening during construction.