This is a very good quality solder less prototype board well known as Breadboard. It has 1 Terminal Strip, 630 Tie-point and 2 Distribution Strips, 200 Tie-point. dimension is 16.5x5.4x0.85(cm). This breadboard has three expansion edges in one side and three groves in another side so you can add many this size board to form a big solder less bread board. All the metal contact points are gold plated and have very good spring action so you will never miss any connection and your circuit will be a flawless circuit.