50Hz Double Sided PCB, Supply Voltage : 4v, 5v, 6v

Double-layer or double-sided PCBs have a base material with a thin layer of conductive metal, like copper, applied to both sides of the board. Holes drilled through the board allow circuits on one side of the board to connect to circuits on the other.The circuits and components of a double-layer PCB board are usually connected in one of two ways: either utilizing a through-hole or with the use of a surface-mount. A through-hole connection means that small wires, known as leads, are fed through the holes, with each end of the leads then soldered to the right component.