https://www.extremedogfence.com/product-category/pet-accessories/tpus/ extremedogfence.com

One size fits most – This collar can be adjusted to accommodate any dog with a neck size of 9 inches up to 28 inches by 3/4 inch wide.
No snag design – The nylon and buckle will not snag or pull at your dog’s neck hair. It’s designed with comfort and durability in mind
Easy release buckle – Though your dog won’t be able to sneak his way out of the collar, the buckle is an easy release system for owner. Just a pinch and it’s off
Simple to Clean – Wash the Rugged Boy collar in warm soapy water. Do not put into washing machine