Made 100% high quality nylon. Higher tensile strength than polyester.Quick and easy release plastic buckleTri-glide for easy size adjustment. Heavy duty D-Ring for leash.Durable: The AirTag holder is made of flexible TPU plastic, waterproof and very durable. The dog collar is made of high quality tough and soft nylon,It is soft enough to keep the dog’s neck breathable and dry. Sturdy buckle and heavy duty metal D-ring prevent the collar from accidentally opening.Designed for AirTag1:1 fit with apple AirTag. It can keep AirTag from falling off, dangling or dog biting. Our dog collar is exactly what your need! Adjustable length:M (2.0 x 34-51cm), L (2.5 x 45-68cm)Package include: Doco dog collar with AirTag holder, AirTag not included. WARNING: Collar is intended for pets only. When securing your pet outdoors, do not use with a tie out. Owners are encouraged to regularly check the tightness of their pet’s collar. Keep pets under supervision and do not leave pets unattended.Installation Instructions1. Slide AirTag through back opening.2. Gently twist until Air Tag is snug.