Round fixture ring used to mount light fixtures in walls and ceilings. The rings convert a 4 In. square box to a 3-1/2 In. round opening with 8-32 threaded mounting tabs for lighting retrofit applications. Angled slots on the covers compensate for up to 1/2 In. of box misalignment on upright framing members. Additionally, the rings are UL and RoHS compliant.