It's a 4 Pin Male Plug-in Screw Terminal Block Connector. It operate on PCB Connector AC 250V 10A. The 4 Pin Pluggable type PCB terminal block is a type of electronic component that provides a secure and reliable way to connect wires to printed circuit boards (PCBs). The refers to the number of connections available on the terminal block. This means that up to eight wires can be connected to the terminal block.