The polystar home theater is designed for optimum performance and long-term durability, this is how you get your groove on! features mp3 playback from usb and card bluetooth built in amplifier fm radio function 2 microphone input speaker units: full range: 5′′ speaker units: woofer: 8′′ output power: 25000w p.m.p.0 impedance: 4 ohms sensitivity: 90db=3db power supply: 230v/50hz