The CMA640B is a decorative finishing ring that visually enhances suspended ceiling installations by covering the hole where the extension column passes through the ceiling tile. Features: The ring is hinged to open for easy installation Compatible with fixed CMS extension columns and fixed CPA columns Specifications: Certifications: UL Listed Color: Black Overall Dimensions (HxWxD): 0.2" x 3.6" x 3.6" Shipping Weight: 1 lbs