WINOMO Detachable Swivel Lobster Clasps Keychains - 20 Sets 20 sets of the lobster clasps 25mm key rings in one package will be sold together. Material: durable metal alloy. Lobster clasp size: Size L (Length: about 37.8mm); Key ring diameter: about 25mm. The lobster clasp has a strong spring loaded snap gate. Pull and hold trigger to open. Realease it and the clasp will automatically close. It can be used for keyrings, keyfobs, charms other crafts.