The normal size of M8 hex nut is 13mm on each side, the height may vary slightly depending on the thickness of the nut thread type, about 80% of the nominal diameter of the screw.
Standard metric hex nut according to ANSI / ASME B18. 2.4. 1M and B18. 2.4. 2MNominal diameter of the nut. x height of the wire through the plates, S thickness MMaximum minimum
|M5 x 0.8||8.00||4.40|
|M6 × 1||10:00 in the morning.||4.90|
|M8 × 1.25||13.00||6. ### 44|
|M8 x 1.25 "||8 mm||.3150|
|M10x1.5||10 mm||. ### 3937|
|1 / 4BSW||13.64|
METRIC NUT SIZE
M stands for metric. Metric threads are specified with the diameter and distance between the threads. For example, the most common screw size used on bicycles is 5x. 8, also known as M5. This size is used for bottle cages, cable anchor bolts, umbrella / bracket eyelets, gear levers, etc. The 5 means the bolt diameter is 5mm.
Metric screw head / wrench size
M8 is about 8mm in diameter, probably just below the waist, (.31496) M10 is about 10mm in diameter (.3937) and M12 is about 12mm (.4724) in diameter. M indicates that the screw is metric and the number after M indicates the size.
The wire height is the distance between the wires in millimeters (measured over the length of the fastener). For example, a wire height of 1.5 means that the distance from one wire to the other is 1.5mm.
The nut fits a 13mm wrench (M8 recommended), the length of the assembly is about 25mm, and the threaded hole is about 21mm. The outside diameter of the thread is about
American machine diameter
The M designation for metric screws indicates the nominal outside diameter of the screw in millimeters (e.g. an M6 screw has a nominal outside diameter of 6 millimeters).
American Nuts and Nuts Table
US Standard Thread Length for Screws
Number of threads
How to determine the screw size and number of threads
Coarse thread screws