carolirala HOT June Dog Doorbells for Dog Training and Housebreaking Clicker Door Bell (1) An easier, better way for your dog to communicate; Instead of hearing barking and scratching, you hear the gentle jingle of Zacro bells Adjustable door bell length for small, medium and large dogs Hang strong Zacro bells from any Doorknob or handle Nylon adjustable doorbell strap and 7 piece 1.4" extra loud stainless stell bells Size:Length 75cm/29.53''(adjustable) Wide: 2cm/0.79"