Souarts Antique Silver Color Heart Shape Claw Lobster Clasps Jewelry Finding 25x12mm Pack of 20pcs The material is zinc alloy Size:about 12mm wide, 25mm long, hole: 4.3mm These lobster claw clasps are well made and highly durable. Excellent size for suspending small items from delicate necklaces, bracelets, earrings, anklets and many ornaments. Every clasp opens and closes easily and smoothly. The closure of curve lobster clasps is very easy and fit for most jump rings and chain.