PoochieBells Dog Potty Training Doorbell, Eco Grosgrain Grey Made from 100% recycled plastic bottles, the Eco- Grosgrain ribbon is woven from yarn made of 100% post consumer recycled materials 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. Portable, no batteries, wires, etc.