Black Kitty Doorbells Simply hang over any door knob Keeps your cat from scratching the door frame when they want to go in or out. Simple and super effective way to teach your Cat to communicate: a.) When it wants to go outside, or, b.) When it wants, in or out, of a closed interior door. [Can also be used to teach them to ask for Cat Nip, or Food.] Beautiful, Loud, Pleasant sounding Bells Height Adjustable (2 Positions) Won't damage wood work USA SELLER Fast Same Day, or Next Business Day Handling [ no waiting 2 months for your items from China ] We strive to provide excellent service and on time deliveries, with either same day, or next business day Handling on all of our items.