Bring some calm back to your yard with PetSafe's outdoor bark control. Shaped like a birdhouse, it can sit anywhere in the yard or hang from a tree. • Emits an ultrasonic tone people can't hear when a dog barks • The tone stops as soon as the barking does • Detects barking in front of the unit, so placement matters • Built to stand up to water A simple step toward quieter days outside.