The GT-TC072B-H055-L1 with SMD-3, 4.5x4.5mm Tactile Switches ROHS is a tactile switch manufactured by G-Switch. It has SMD as its structure, with a size of 3, 4.5x4.5 millimeters, and it complies with the standards of ROHS. It's a type of switch which is used to start and stop a circuit when a person presses the button. This switch provides a tactile sensation with each operation and has a long lifespan, making it suitable for many applications. It is widely used in the automotive, medical, consumer, and industrial markets.