Two Source, 6.5", Amplified Drop Ceiling Speaker with Bluetooth on a 2X2 tile and backcan assembly delivers up to 40 watts power directly to the speaker. Each powered speaker can drive three additional speakers (2X2IC6NA). 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 and Volume Control included. Available also in models without bluetooth features.