★ Flat key ring size : Inner diameter: 4/5" (28mm),outer diameter: 1.25 " (32mm) ★ Durable material : key-chain rings with electroplated surface, anti-rust and anti-erosion, these key-chain rings are made of iron material, hard and strong. ★ Safe & use : These Flat Key Rings tight closure ensures security, and never worry about slipping off from key ring. ★ Excellent connecting accessory : The round flat split ring is good for connecting clasps, charms, links and other ornaments; Easy and convenient to carry. ★ Widely use : Suitable for a wide range of uses. In addition to holding keys, they can also be used to carry membership cards, connect fasteners, pendants, links, clasps, charms, and dog tag rings.