Mesh harness with single buckle closure and D ring for leash. These mesh harnesses in XS are one of the best options I've found so far for the super tiny ones. It lists as 8" at the neck but this 8" seems much smaller than the 8" on the adjustable neck versions - - they are both 8", I measured. Nice and soft and light. I wish I'd found these when the puppy was still small! I'd say these would be great for the 4-5 pound bracket but follow those measurements of 8" static neckline and 11"-13" at the mid-waist girth.