High quality material: The upgraded locking pin is made of high-quality copper on the back, which is and sturdy, and can firmly lock your pin, ensuring that it remains safe and in place. Easy to secure your pins: The back of these locking pins provides an additional layer of security for your pins, ensuring they are securely secured. Unlike traditional needle backs, these locking needle backs have a buckle design that can prevent your needle from falling off and losing. Easy to use: With a spring design, pins can be easily locked and removed without the need for tools. Simply push the base to lock and secure the pins, and pull to release the lock and remove it. This makes these locking pin backs an excellent choice for those who frequently wear and replace pins. Widely used: Pin backing is suitable for DIY projects such as pins, lapel pins, nameplates, display books, lanyards, bags, vests, hats, denim buckles, badges, backpacks, enamel pins, etc. Value for money: Provides sufficient locking pin backs. The size of the pin backs is 0.4 inches in diameter and 0.25 inches in height. They are compatible with most standard pin sizes and styles, and can meet all your pin needs.