No Pull No Choke - A martingale collar is formed at the neck circumference through the attachment of a leash. When the dog tries to pull or suddenly runs forward, you can immediately control the dog through the leash! Curved design ensures a choke-free dog, padded cushion keeps dog comfortable Comfortable Material - The harness is made of skin-friendly fabric, soft, breathable, and lightweight. Suitable for all day & all weather wearing Reflective in the Darkness - Reflective strips around front and back straps. It enhances safety for night walking or training Easy to Wear & Adjust - The harness has two quick-release buckles, and four adjustment clips, even new dog parents, can easily and quickly get the hang of putting it on and adjusting it Size Guide - [S: neck girth is max 15", chest girth is 14"-17.7"]; [M: neck girth is max 17", chest girth is 17"-20.8"]; [L: neck girth is max 19.7", chest girth is 19.5"-24"]. Please measure your dog's neck girth and chest girth, then refer above size guide to choose a suitable size Dog harness and leash set for daily walking and training