suitable for most cases involving voice control.It receives configuration commands or responds through serial port interface. With this module, we can control cars or other electrical devices by voice.It can store 15 pieces of voice instruction.Those 15 pieces are divided into 3 groups, with 5 in one group. First we should record the voice instructions group by group.After that, we should import one group by serial command before it could recognize the 5 voice instructions within that group.If we need to implement instructions in other groups, we should import the group first. This module is speaker independent. If your friend speaks the voice instruction instead of you, it may not identify the instruction.Voltage: 4.5-5.5VCurrent: Less than 40mADigital Interface: 5V TTL level UART interfaceAnalog Interface: 3.5mm mono-channel microphone connector + microphone pin interface Recognition accuracy: 99% (under ideal environment)colour:blackMaterial:Plastic + metalsize:3.1*5*1.5CMPackage Contents:1*Voice Recognition Module1*MicrophonePlease note that speaker independence requires strictly good MIC. The MIC we supply may be not good enough for it to be speaker-independent.Only the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.