Product Description A plastic ceiling diffuser with incorporated ceiling box. For residential and light commercial use and offered in 8x8 square, 6x6 square, and round. One piece grille, damper box and lightning fast installation. Designed for 1-man installation only working below the ceiling, they offer convenience and speed. Virtually air tight butterfly damper rubber gasket delivers superior seal when closed. High grade polymer grille resists breakage, scratching, yellowing and fading. Grille/Damper ceiling diffuser, HVAC, 6" Round, Grille/Damper/Box 4,5,6"; mounting clip accommodates thicknesses up to 11/4"; damper handle allows smooth, easy turning adjustment from below for fully open to tightly closed position. For residential/light commercial use and offered in 8"x 8" square, 6x6" square, & 6" and 8" round. FOR THE TRADESMAN: RectorSeal is recognized as a leading provider of quality solutions for the professional trades serving heating, ventilation, and air conditioning (HVAC/R), plumbing, electrical, and construction markets. From the Manufacturer Model MV ceiling diffuser with round grille Our Model MV ceiling diffuser line is a snap to install in any ceiling. Quick tear off bands allow for easy size changes and our swinging clips will fasten the assembly into the ceiling in seconds! Made from high impact polymers and featuring a virtually airtight damper for winter shut off and/or volume control makes them a great fit in any application.