With a rough side for trimming, and a smooth side to protect sensitive birdie feet, Safety perches can help keep nails and beaks in top condition. Extra small size is approximately 4-1/2 inches long and measures approximately 5/8 inch in diameter. Appropriate for extra small birds such as finches, canaries and small budgies, lovebirds, and similar sized birds. Non-toxic and safe for your bird. No sanded surface to harm feet.Stimulates leg muscles and promotes healthy feet.