The MB-2 is our most flexible mobile solution to keep your
pet safe inside. This transmitter can be used either with or
without a boundary wire. You can install the MB-2 with a
wire to protect a large defined indoor area or you can use
it without a wire for greater flexibility to protect smaller
areas up to 13 feet in diameter (6 1/2 feet from center).
Works with all DogWatch FM receivers.