... system USB,SD,FM function OEM service Magnetically shielded Hot dance 4.1ch disco loudspeaker 1.Hot 4.1 home theater ... , effectively eliminate resonance and cabinet noise5. With Standby,Input,Menu,VOL+,VOL- keys on the front panel. Output power20W+15W*2=50W ... shielded Carton box size 386*237*463mm G.W 6.0KG 20FT660 sets 40FT1380sets 40HQ1632 sets Hot dance 4.1ch disco loudspeaker