EzyDog Quick Fit Custom Fit Adjustable Dog Harness SIMPLE ONE-CLICK FIT SYSTEM: Our Patent Pending EzyDog One-Click Fit System lets you know if you have the right fit without all the frustrations that fitting other harnesses can cause. As easy to use as a collar, with all the benefits of a harness. NEOPRENE PADDED CHEST SLEEVE: Our premium waterproof neoprene chest sleeve covers the adjustable chest strap for a durable and comfortable fit on your dog. REFLECTIVE SAFETY STITCHING THROUGHOUT: We've incorporated high-visibility reflective stitching throughout our award-winning design to increase nighttime visibility and safety for both you and your dog. QUICK-CLIP BUCKLE SYSTEM: Our heavy-duty EzyDog Quick-Clip Buckles provide you with fast and easy on and off for hassle-free fun. SELECT THE BEST SIZE: Fit matters! If you are close to the end of a size, choose the larger of two sizes:GIRTH in inches: XXS 12-15, XS 15-18, SM 18-21.5, MD 21.5-26.5,LG 26.5-33, XL 33-42