Input voltage: DC12-24V Number of channels: two channels Chip:Two NE5532 size:96*39*16 MM colour:blue Material:Metal + pc Package Contents: 1 * XH-A901 NE5532 Tone Board 1 * 3P Audio cable 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.