Product details:

This system creates a customizable wireless fence using GPS, and you can mark the boundary with the included flags. With the included collar, your dog will learn to stay within the fence thanks to the adjustable levels of sound, vibration, or shock stimuli that go off when he crosses the barrier. The stimuli gently escalate the farther your pup strays, but it automatically corrects to safe levels—even if your pal stays outside of the barrier for a while—so he will never get hurt by the stimuli. Compatible with multiple collars, you can easily contain your pal in the yard, on camping trips, and more!