Thank you so much for browsing and good luck with your purchase! Material:Aluminium Alloy Size:Thread Diameter*Screw Length,I uploaded the size chart,the error range is no more than 0.3mm. Quantity:If the stock is not enough,please leave a message. Purpose Electronic products: Used to hold small parts in electronic devices for quick assembly and disassembly. Commonly used in the assembly process of electronic products such as mobile phones, laptops and digital cameras. Home Decoration: Used for the installation of furniture and home décor, such as hanging murals, installing wall shelves, etc.