Size Guide Size Chest Size S 9.84"–11.81" SM 11.81"–13.78" M 13.78"–15.75" ML 15.75"–18.11" L 18.11"–20.47" XL 20.47"–23.62" Sizing Note: This harness runs slightly smaller due to its thicker fabric. If your dog is between sizes or will wear it over a sweater or coat, size up. Soft & Breathable: Soft corduroy exterior with breathable air-mesh lining for everyday comfort. Easy On & Off: One-buckle design makes getting ready for walks quick and simple. Comfortable Fit: Designed to sit away from the underarms to help reduce rubbing and discomfort. Streamlined Design: Lightweight, minimalist silhouette that layers easily over sweaters and jackets. Complete the Look: Pair with the matching leash for a polished everyday style. Please Note: The Buckle Up Easy Harness is not adjustable. Measure your dog’s chest carefully before ordering. Fit may vary depending on body shape and fur length.