Basic Introduction Compared to the traditional choke collar that is aggressive and uses uncontrolled force to correct negative behaviors. Wellbro martingale-style collar tightens enough under tension to provide a subtle controlled training cue to your dog. The purpose of this is not to choke a dog, but to prevent a dog from escape the collar because it offers limited closure. Endorsed by thousands of trainers, our humane dog training collars are much safer and more effective. Specifications 1.Material: Premium nylon fabric+plastic buckle and clip+stainless steel chain 2.Collar Size: Available in adjustable sizes S/M/L 3.Color Option: Black and Gray 4.Net Weight: S: 80g; M: 140g; L: 145g Main Features 1.More Control: Martingale collar provides more control when used on dogs that are prone to pulling and helps the dog learn some basic commands. The limited cinch collar is designed to provides limited correction with an audible cue. 2.Reflective: The new style reflective dog collar enhances security and avoid accidents for its good visibility at night walking; 3.Durable: Solid stainless steel and is heavy duty and rust-proof and nylon woven webbing is strong with good color fastness. 4.No Choke: This martingale collar has a limited closure design and the convenience of adjustable sizing, which ensures that it won’t fully close or choke a dog as a choke collar does, it only contracts so it stays snugly on the dog.