3inch PREMIUM FULL-RANGE IN-CEILING SPEAKERS. One 3inch (76.2mm) full-range high-extrusion, high-fidelity polypropylene driver with butyl rubber surround. Weatherized components for indoor/outdoor applications. Shallow 3.5inch (88.9mm) deep all-steel backcan with integrated driver and baffle configuration. Ultra-compact design with a total visible footprint of less than 6.3 inch (160.6 mm)diameter. Rapid installation, blind-mount, fixed-wing mounting mechanism with constant tension design affixing to wall thicknesses ranging from 0.1in. (2.5mm) to 1.5in. (38.1mm). Corrosion-resistant, powder-coated aluminum grille with snap fit attachment. Ceramic input terminal accepts up to 10 gauge plenum rated signal wire and includes thermal fuse.