The Rogz Step In Harness is made from high quality nylon with reflective webbing. Simply put your dog's legs through the two leg straps and with a single clip your dog is secured. The clip also has a security lock on it. Plus there are also two rings to attach your lead on either side of the clip to take unnecessary pressure off, making for a more durable harness. The design of the Step In Harness takes the tension off of your dog's neck while walking. Medium is 42 -61cm Girth.