Abstract: According to the present invention, there is provided an electrical junction box for mounting an electrical fan to a structure which junction box includes a channel further including longitudinal teeth that engage the rafter or other structural member to which the fan is to be attached. The engagement of the mounting box channel with the rafter resists lateral movement in a more substantial fashion thereby assuring that less stress is placed on the electrical box mounting screw(s). The longitudinal teeth positively engage the rafter when the electrical box is slideably inserted over the rafter. A hole is provided for further securing the electrical box to the rafter with a more conventional screw.