PoochieBells Dog Potty Training Doorbell, Olive Easy to Train & Use Quickly - 95% success rate Reinforced bells which are extra smooth, snapped & looped safely into place so that they won't be pulled or fall off, heavy duty designer durable grosgrain ribbon, strategically placed for small and large breeds. No more whining, barking or waiting by the door! An intelligent, proven and highly effective training choice. Recommended by professional trainers. Training Instructions Included with Your Order Portable, no batteries, wires, etc.