The AMP-BT2SIC6 is a 6.5" two source amplified drop ceiling speaker with Bluetooth features, deliver up to 40W power directly to the speaker. Each powered speaker (AMP-BT2SIC6) can drive three additional speakers (IC6). One line can drive up to 10 self-amplified speakers. Lower noise feature and protection from shorts and overheating. 15 Volt DC level 5 power supply included.