... .Components: (1) loudspeaker, (2) on/off button, (3) charging indicator light(red), (4) read out indicator light(blue), (5) optical camera, ... also be used for recording.4. download5. system updatedAudio Pen and Book: Delecate packaging: Main technical parameters: Name ... ×20mmweight38gloudspeaker8Ω,0.5WThe service we offerd:1.Pen design, mold development;2.PCB board design and development;3.The ...