10pcs Pin Keepers with Secure Lock Backs and a Wrench Tool. Each pin keeper is approximately 5mm in diameter and 6mm in height. Made from durable, rust-proof nickel-plated copper, these bulk pin backs have a smooth surface and securely lock your pins in place. Never worry about pins falling off again! These keepers provide a reliable replacement for broken mechanisms, ensuring your items stay put. Keep your pins secure and organized with this practical set. The small screw design eliminates fiddly parts. How to Use: Insert the black screw into the center hole. Use the small wrench to screw it in securely. Attach to your brooch or medal, aligning the holes. Gradually tighten the black screw with the wrench to ensure a firm hold. Item Type: Pin Keepers Material: Brass Color: Silver Quantity: 10 sets. Note: Size measurements may have a 0-3mm error, which is normal. Colors may vary slightly due to monitor differences. Package Includes: 10 sets x Pin Secure Locks.