The reliable and rugged 3M Overhead Projector Model 1820 takes years of classroom use, and yet its stylish enough for any executive boardroom. A strong 2,700 - lumen light output delivers bright presentations in various lighting conditions, and a wide-angle singlet lens projects large, clear images in the smallest rooms. The closed-head design protects the lens from dust, and smudges. A lamp ejector makes replacing lamps simple, and a thermal-protection circuit prevents the unit from overheating. Features also include accessible power switch that puts the controls where they count, at fingertip reach, fold-down post, and handy power-cord wrap. Of course, all parts and labor are backed by a five-year warranty from 3M - your first choice in overhead projectors for more than four decades.