Tannoy DVS 401 Coaxial Surface-Mount Loudspeaker with Transformer for Installation Applications (Pair, White) - 4"The DVS 401 WH is a coaxial surface mount loudspeaker engineered to provide superb audio performance in both background and foreground music sound systems. Ideally suited for a wide variety of applications, from restaurants and hotels to houses of worship and businesses of all types, the DVS 401 WH offers the power handling, wide frequency response and low distortion typically found in more expensive products. EN 54 24 certification for fire detection