Hardened nail specifically designed for fixing to masonry and concrete blocks. Countersunk head for flush fit 35 sharp point for easy penetration Hardened carbon steel for extra strength Bright zinc plated for internal use" Shank Dia. mm: 2.50 Length mm: 50 Finish: Zinc Material: Hardened Carbon Steel Approx. Pcs Per 1kg: N/A Timco Masonry Nails - Zinc (Size 50 x 2.50 - 100 Pieces) in Silver