The Bogen HFSF1 High-Fidelity, Small-Footprint Ceiling Loudspeaker delivers superior sound in a very compact enclosure. The speaker measures 7-1/4" diameter and mounts easily in all types of ceilings - including existing hard-surfaced types and suspended type. Several levels of power output can be controlled directly from the front baffle via a rotary tap selector switch under the grille. The low-distortion, coaxial-design speaker, coupled with a computer-matched venting system, delivers superb fidelity for music as well as high intelligibility for voice reinforcement. Coupled with the Bogen CSUB Ceiling Subwoofer, it provides the perfect solution for environments that require the highest-quality sound with minimal visual impact.