M16 Galvanised Heavy Hexagon Nut - A194 Grade 4 Tapped Oversize (Since hot-dip galvanizing typically adds 2.2 to 5 mils of thickness to the threaded portion of a fastener, galvanized heavy hex nuts are tapped oversize to compensate for the corrosion resistant coating on the thread of the bolt) Quenched & tempered medium carbon-molybdenum heavy hex nuts Where: e = point to point m = thickness s = across flats d = Thread e - 26.75 mm (min) m - 15.57 mm (min) s - 23.67 mm (min) d - M16 Thread Pitch - 2.00 mm