Lupine 1/2" H-Style Harness- A very secure harness for walking cats or small dogs. The adjustable collar buckles around the neck and is joined to an adjustable girth. To determine correct size, measure pet snugly around ribcage, close to the elbow, then add an extra 5-10 % for comfort. In girth size ranges 9"-14" and 12"-20". Owners with concerns about their dogs neck or back may want to consider the 1/2" Roman-Style-Harness.