COMPATIBLE WITH APPLE AIRTAG: Our cat collar is specially designed for the Apple Airtag GPS tracker and will not work with any other device. Comes with an Airtag case, waterproof and shockproof. EASY TO USE: Put the Airtag GPS tracker into the cat collar holder, then you can use your iPhone to track your pet. The slip-on design can be widely used for cat collars, dog collars, and anything with a shoulder strap. BELL AND REFLECTIVE STRIP: The Airtag cat collar comes with a clear and loud bell, allowing you to get your cat's location in real time. Reflective design allows your pet to be seen in dark environments. SAFETY RELEASE BUCKLE: It adopts separate safety buckle design, which can be released when pulled hard, and it is easy to open and close, so that your pet can easily break free when trapped, and it is more safe to run indoors. ADJUSTABLE COLLAR SIZE: The length is adjustable to fit pet neck sizes from 8.66 to 13.78 inches. 0.4 inches wide, fits most cats, puppies and small pets. Please measure your cat's neck size before purchasing.