Abstract: A support bracket for connecting an auxiliary electrical unit to an in situ unit, comprising a mounting means for locating between the in situ unit and an outlet box (hereinafter referred to as a patress box) or a wall to which the in situ unit is originally mounted, and for mounting the in situ unit to the patress box or wall. A support means extends from the mounting means for supporting the auxiliary unit. A cable accommodating means is provided for accommodating a cable from the patress box or wall through the support bracket to the in situ unit. One of the cable accommodating means and the mounting means is adapted to permit location of the mounting means between the in situ unit and the patress box or wall, and for permitting mounting of the in situ unit on the mounting means without disconnection of the cable from the in situ unit. A communicating means is provided for accommodating an electrical wire from the in situ unit to the auxiliary unit.