Better Communication: Instead of barking and scratching, you hear the soft chime of the doorbell. Adjustable length: You can adjust the length of the bell between 30.5 and 32.5 inches according to your dog’s needs. DURABLE: Made up of a nylon strap and 7 super loud 1.4" stainless steel bells, this doorbell is built to last. EASY TO USE: Simply adjust the length of the doorbell and hang it on the door handle. Match: Comes with a training clicker and litter bag to help you train your dog and store dog litter. Quantity Shipped: 2 pieces