John Deere 21H1391 0.164" X 5/8" Cylindrical Head Screw is designed for secure fastening in various applications. It features a head diameter of 8.18 mm (5/16 in) and a length of 15.88 mm (5/8 in) with UNC2A threading to ensure reliable connections. The screw includes a drive type H and a head height of 2.92 mm (0.12 in), providing optimal performance even in demanding environments. Made from high-quality steel, this screw durability and strength, while its zinc coating resists corrosion and enhances longevity. Model Number: 21H1391