A board-to-board connector is a component that connects or disconnects a circuit board and components, etc., by attaching it to the circuit board. Mainly used for notebook computers, mobile devices, and information and communication devices, board-to-board connectors include vertical connections, stacking connections, horizontal connections, etc. and various combinations of connectors are possible by combining connectors. Some have various functions, such as being vibration-resistant, impact resistant, having a high retention of connection parts, etc. Many connectors are square, and male, female and male / female are also used, so it is necessary to select a connector according to the circuit board and components to be connected.