[Bird Foot Ring] Used to mark pigeons or birds born in 2023 so that they have their own ID numbers.Bright colors and numbers make it easy to identify.Widely use these ring bands to identify similar looking birds,keep different breeds apart.[Material of racing pigeon ring] 100% Brand new Adopting high quality aluminum and plastic material,which is durable,non-toxic and extensible for long term use, harmless and safe for birds.Our carefully selected pigeon leg rings are all made by quality plastic material, which is reusable and safe to use.[Pigeon Leg Ring Size]Inner Diameter (Minimum): About 8mm/0.4 inches.Outer Diameter: Approx. 11mm/0.43".Height: Approx. 11 mm/0.43 inches[Wide Application]: Leg rings can help you separate different breeds, separate hatching, mark suspicious pigeons, birds, etc.[Satisfactory after-sales service]: If you have any questions about our products, please feel free to contact us, we will provide you with the best service.