What is this?These pin backs locking pin keepers are made of copper, with a smooth touch and can be locked without the need for tools. The sturdy structure can firmly lock your pin, ensuring long-term use, reducing wear and tear, and not easily falling off. Suitable for pins, nameplates, display books, ornaments, hats, badges, etc.What will I get?This Locking Clasp is in size of:Diameter: 6mm/0.23 inchHeight: 5mm/0.2 inchHole Diameter: 2mmThread Specification: M3 x 0.5Color:GoldMaterial: CopperIn the Package of: 50 x Pin Backs, 50 x Screws, 4 x WrenchIs there any advantages of the product?This Pin Backs is compact and easy to carry, sturdy and durable, suitable for various occasions, easy to use, and can keep your lapel pins without tools, badges, and brooches securely in place.