Blue -The tracker is not included (excl. airtag) Cat collar, cat collar with bell and safety closure, adjustable cat collar, cat collar with box [Designed for Apple Airtag:] Cat collar for Apple Airtag, you will receive a nylon cat collar with bell and an Apple Airtag case (Apple Airtag not included). [Find your cat:] You can place your Apple Airtag in the waterproof silicone Airtag case that comes with the collar and locate your cat on your phone, or you can locate your cat using the bell on the collar. [ Automatic safety device:] The cat collar is made of safe and durable stitched nylon and features an automatic release safety device that releases with a simple pull to prevent your cat from choking and to keep your pet safe . [Adjustable size:] The cat collar is 0.39 inches wide and the length can be adjusted between 8.6 inches and 13.4 inches to fit most small pets such as kittens, puppies and plush Pomeranians.