material:taiwan chimei 757 ABS battery up time:over 8H size:77*73*33MM MP3 available N/W:165G Max effective distance:400㎡ OEM available IC max power output:RMS10W loudspeaker output:3-5W frequency response:150HZ-10,000HZ+-1DB current consumption:150mA input signal:wire mic.(-20DB 600) voltage:DC 7.4V internal lithium battery:battery pack,Seiko IC chip,Dual Protection