Crossbars are used to mount light fixtures to the electrical junction box. Kit contains an assortment of the most commonly used items for a screw collar loop mount. Requires a canopy with 1-1/16 center hole. What's Included: (1) Flat Crossbar - 1/4 IP ; (1) Screw Collar Loop; (1) 1/4 IP Lock Nut; (1) 3/8 IP Lock Nut; (1) 1/4 IP X 3/8 IP Hickey; (1) 1/4 IP x 1 1/2" Nipple; (2) 8-32 x 1/2 Mounting ScrewsScrew collar loop crossbar kit4 inches longCenter tapped 1/4 IP