Square Cover. Plaster Ring, Mud Ring | 4 11/16 in Square, 2 in Raised Single Device Tile Cover | An Affordable Digital Lighting Platform Designed to Deliver General Ambient Lighting for Recessed-Ceiling Applications in Schools, Offices and Hospitals. Built on the Tried-and-True Gt Troffer Platform, the Led Technology Ensures Reliable Color Consistency | Use Through Knockout to Connect Box to Conduit Coupling; Use With a Locknut to Connect Two Boxes Side by Side or Back to Back; Use With a Locknut to Connect Fixture Housings in Continuous Runs; Rigid Conduit Threads (Nps)Furbay Electric Supp