ZINC PLATED BLIND RIVET NUTS CYLINDRICAL SHANK CLOSED END FLAT HEAD. Blind Rivet Nuts Cylindrical Shank Closed End Flat Head. M8 (8mm) 11 mm 16 mm 1 - 3.2 mm 1.4 - 1.6 mm 24.5 mm. High quality rivet nuts made of zinc plated steel and toAN 324 standards.