Our Patented, made-in-the-USA Birdy Bootie protective shoe for birds is designed to provide superior coverage and cushioning for chickens, ducks and geese with injured feet or bumble foot. Our Birdy Bootie is made of high quality human-grade orthotic neoprene to provide cushioning and to protect wounds from dirt. The booties fasten around the foot and ankle with strong hook and loop. The open-shoe design with seams on the inside provides both adequate space for toes and structure to enable circulation of air. Unlike "one-shape fits all" waterfowl shoes, our Birdy Bootie is specifically designed for fit and comfort: The left bootie is shaped to be worn on the left foot and the right shoe is shaped to be worn on the right foot. Note: we recommend that wounded pets be seen by a veterinarian. DO NOT OVER TIGHTEN. DO NOT USE IN HOT WEATHER (birds cool themselves through their feet). SIZING INSIDE FROM WIDEST POINT (OUTER TOE TO OUTER TOE): Small is 3" across, Medium is 3.5" across and large is 4.5" across.