Contech 300000408 WaterDog Automatic Outdoor Pet Drinking Fountain Your dog will always have fresh clean water WaterDog will ensure your dog can always help itself to fresh clean and healthy water whenever it likes Sonar proximity sensor automatically turns the water on when your dog is within 3' and off again when your dog walks away Never worry again about stagnant, unhealthy or empty water bowls Installs easily on any outdoor faucet