Collar fits 9in - 12in neck. There are no standard sizes for dog collars. Please be sure to measure your dog's neck for correct size. Measure around your dog's neck (with string or tape measure) snugly where you want the collar to lay. If you have any questions or problems with sizes please give us a call before ordering. 256-974-0700 Breed Recommendation: Shih Tzu, Chihuahua, or Yorkie Made in U.S.A. with top quality hardware - The 1/2' Extra Small features our Feather Weight polyester webbing and our top quality 1/2' hardware Traditional martingale collar has no buckle - Featherweight collars are not intended to be used with animals who pull excessively or tie out systems