Important: This is a replacement magnet component only, designed to attach to your cat flap door. This is not a complete cat flap unit. This magnet is compatible with the following Staywell cat flap models: 16, 17, 18, 19, 20, 21, 22, 30, 31, 32, 916, 917, 918, 919, and 932. Easy to install – simply attach to your existing flap. Please note: Take care with the polarity of the magnet during insta..