If you have dogs who bark at everything they see the NPS No Shock Bark Collar will bring peace and tranquility to your life. Two of my rescue dogs like to look out the window and bark at rabbits, deer, cars, walkers, and anything else that moves. Since they have been wearing these no shock bark collars all barking stops in 15 seconds or less. It is a safe and humane way to control your dog’s barking. The collar is one size fits all and is easy to adjust and trim to fit your dog. This is the best way I’ve found to prevent my dogs from continuously barking. As an Amazon Associate, I earn from qualifying purchases.