Size is Large Racing Flames other images are show for illustration purposes. Doggles Sizing. How to measure your dog: Back Strap and Frame Length: Measure the entire head circumference, across the eyes and around under the ears. Chin Strap: Start just under one ear, under the chin, and back up to the other ear (like a helmet strap). Doggles ILS are an extremely unique product with the following characteristics: Polycarbonate (shatterproof), anti-fog, 100% UV protection lenses. Extremely flexible rubber frame. Elastic adjustable straps - head and chin. Foam lined frame for extra comfort. Extra deep lens cup keeps the lenses away from the eyes. Patented. Vet recommended! Doggles ILS are the first and only protective eyewear designed just for dogs! Doggles ILS (Interchangeable Lens System) the very best in pet eyewear. For true eye protection or fashion, your pet deserves the very best. Doggles offer 100% UV protection, shatter-proof lenses, and anti-fog treatment on the inside of the lenses. Lenses on the ILS style are interchangeable and replaceable. This style is suited to all dog head shapes and sizes. Whether your best friend accompanies you on a motorcycle ride, hangs their head out of the truck or car, loves to sunbathe, or is sensitive to light, Doggles will be sure to keep their precious eyes safe. You can rest assured, and theyll love the extra attention! If you have any questions regarding your order or you are not satisfied with your purchase, please contact us before leaving feedback so we may resolve your concern. Thank you for your business.