Precise Sizing for Medium Dogs: Dog collar neck 14"-21", Width 1", Size Medium; Please make sure to leave ONLY 2 finger between the collar and the dog neck (properly fitting collar won't leave any room for your dog to chew and pet won't slip out of their collar) Durable Construction Materials: Silky soft polyester webbing dog collar with aluminum and stainless steel hardware for superior strength won't loose or fray; original geometric pattern, simple yet stylish, not easily faded Martingale Training Design: Martingale style collars WITHOUT THE BUCKLE. Dog training collar designed for escape prevention and behavior correction. If you want to stop your dog's incorrect behavior, the collar will tighten as you pull, giving you gentle control over your pet Escape Prevention Feature: This collar prevents dogs from slipping out, suitable for hard-headed pups, puppies, and service dogs; The limited closure prevents it from becoming too tight, ensuring a secure and comfortable experience Professional Craftsmanship: Each dog collar crafted with attention to detail by professionals who understand the importance of your pet's comfort and safety. Means you can trust in the quality and durability of dog collar Stylish Firework Dots Pattern: Features a colorful oil painting pattern series with Firework Dots design in black, combining unique beauty and fashion features that make your pet stand out during walks and training sessions We professionally produce high-quality, safe and comfortable pet supplies, focused on every detail of our products, combining unique beauty and fashion features, the premium choice for pet lovers.