Airtag Tracker Collar: Does your dog like hanging out and sometimes hard to find them? Just put your airtag into the collar with holder to build a GPS Tracker for your dog, then you can track your pets easily through the Find My app on iPhone. Waterproof Collar Holder: The apple air tag dog collar holder is made of soft liquid silicone material, easy to clean. Waterproof, scratch-resistant, and with drop protection performance. Slide-on installed design, not shaking under the pet's collar. Adjustable Collar Size: There are 3 different options of collars size for you to choose from. (S length from 9.84-15.75" 0.6width, M 11.81-19.69" 0.79width, L 15.75-23.62" 0.98width). Please choose the most comfortable size for your dog. Safe Dog Collar: The air tag collar comes with a quick snap buckle and D-ring design. The buckle is durable and not easy to break, convenient for you to take your pets out for walking or other outdoor activities. Imitation Nylon Collar: Made of high-quality imitation nylon material, it's much soft than usual nylon and easier to keep the dog's neck breathable and dry. Suitable for most small medium and large dogs.