Light micrograph of tracks and pins in a multilayer printed circuit for the CPU socket, on the back side of a motherboard. There is a through-hole technology for vertical interconnected access. The tracks are orange colored. The socket tin contacts are very visible; they present the tip of the pins soldered onto the socket, and some are also connected with tracks from the printed circuit. Field of view size: 9.5 x 14.2 mm (0.37 x 0.56 in)