21 pc speaker system stereo pc speaker series logitech z colour black transmission mode cable analogue inputs 35mm jack input line in stereo rca input analogue outputs 35mm phone jack power rating 40 watt effective output 80 watt frequency response 55 20000 hz speaker system 21 system system active suitable for desktop pc notebook speaker controls corded remote control feature power switch satellite feature 2 way system rated power front 2