Spiral leg bands are molded plastic rings that uncoil for placement around a bird's leg and then close back to their original spiral shape. No tools are required to attach or remove them, so keepers can fit or adjust a band by hand. Each package includes multiple bands in assorted color combinations, allowing different colors to represent different ages, bloodlines, or groups within a flock. The bands are intended to sit loosely on the leg rather than snug, since a tight fit can restrict movement as a bird grows. They are produced in the United States and are suited to backyard flocks as well as birds shown at poultry exhibitions and fairs. Bands should be checked periodically and removed or replaced if they become tight on a growing bird.