The BOSE's FREESPACE DS 40F is a flush-mount loudspeaker with a single 4.5" full-range driver with a 125° conical coverage pattern for clear foreground/background music and speech reproduction. It can handle continuous power of up to 40 watts (160 watts peak) and has a maximum peak SPL of 109 decibels. This public address system has an integrated multi-tap transformer that can be tuned to a variety of 70V/100V voltages using a thumbwheel beneath the grille.