The BS-680FC speaker has a strong all-metal body and is ideally suited for emergency broadcasting (voice alarm system) applications. The 6 (16cm) double cone speaker unit ensures high quality sound. It can be quickly and easily installed in either a horizontal or a vertical orientation. Either concealed in-wall wiring or exposed wiring can be used for speaker cable connection. A push-in type input connector allows easy cable connections and bridge wiring. The selectable input impedance can be easily adjusted by changing the top position of the unit’s transformer. Both wall and in-wall mounting are possible. The innovative structural design is based on the Golden Ratio (1: 1.618) and also permits direct wall installation with screws making the speaker unit resistant to falling even if outward force is applied to it. Two ceramic screw terminal blocks (1 cable to 1 connection type) make bridge connection easier.