The IR Transmitter can be used with any straight CW keyer, or bug (e.g. Vibroplex bug) - just plug in and go! It does not contain a keyer electronic! It features a sturdy aluminum casing and has a built-in tone generator that can be adjusted to seven different pitches or switched completely silent. A red 3 mm LED serves as a visual indication of the Morse code. Power is supplied by a CR 2032 lithium cell. The IR Transmitter works with any of our IR Receiver and IR Sensor models.