The 8 inch dual cone speaker with beam clamp, model BC810-72, provides an efficient way to mount to  a beams or girder in open ceiling environments. The 8-inch 15W dual cone driver with wired dual voltage (25V/70V) 5W transformer includes a round enclosure and grille to provide clear, reliable performance for paging or background music. Transformer taps at .25, .5, 1, 2, and 5W.