This is an extra large lobster clasp in sterling silver, 18mm long, with ring. A lobster clasp is a type of clasp that is often used in jewelry making and other crafts. It is a spring-loaded clasp that consists of two hinged halves that can be opened and closed like a lobster claw. The halves of the clasp are connected to the ends of a necklace, bracelet, or another piece of jewelry, and the spring mechanism allows the clasp to hold the jewelry securely in place when it is closed. Lobster clasps are popular because they are easy to use, and they provide a secure hold without being too difficult to open. They are often used in place of traditional jump rings or hook-and-eye clasps, as they are more secure and less prone to coming undone.