Large. 1" Width. Fits dogs similar in size to a standard German Shepherd. Strap A: Adjusts 22 - 38"; Strap B: Adjusts 16 - 26” - Harnesses are adjustable around both the neck (A) and chest (B). Kwik Klip buckles allow harness to be fitted and removed quickly. These comfortable harnesses can grow with the dog. OmniPet Kwik Klip Adjustable Nylon Harnesses work great with OmniPet Leads available in nylon, leather and more.