Country Brook Design Nylon Step-in Dog Harness Collar fits 14in-24in Neck/14in-24in Girth. There are no standard sizes for dog collars. Please be sure to measure your dog for correct size. Measure around your dog (with string or tape measure) snugly where you want the harness to lay. If you have any questions or problems with sizes please give us a call before ordering. 256-974-0700 Breed Recommendation: Boston Terrier, Dachshund, or Pug Made in U.S.A. with top quality hardware Made with 100% nylon webbing