Hex nuts, also known as hexagonal nuts, are a common type of fastener used in various industries for securing bolts and screws. In the metric system, they come in a range of sizes to accommodate different applications and requirements. Metric hex nut sizes are specified primarily by two dimensions the nominal diameter and the thickness or height. The nominal diameter refers to the outer width of the hexagon, which corresponds to the size of the bolt or screw it will fit. This is usually measured in millimeters (mm). The thickness, or height, is the distance from one flat side of the nut to the other, and it affects the amount of space available for the nut to be tightened. The most common metric hex nut sizes start at M3, with a diameter of 3mm, and go up to M64, with a diameter of 64mm. Each size increment typically corresponds to a 1mm increase in diameter. For instance, moving from M4 to M5 indicates an increase in size from 4mm to 5mm. The thickness of the nuts generally increases along with the diameter, but not always proportionally. In addition to the size, hex nuts are also classified by their strength grade, indicated by a number followed by an M. Grades such as 4.6, 86, 86, 86, 8hex nut sizes metric.8, 10.9, and 12.9 denote the tensile strength of the nut, with higher numbers representing greater strength. These grades are essential for ensuring the nut can withstand the forces applied in its specific application. Hex nuts are widely used due to their versatility and ease of use. They can be tightened or loosened using a wrench or spanner, with the six-sided shape providing a secure grip and preventing slippage. Their metric sizes make them suitable for various industries, from automotive and construction to machinery and electronics. In conclusion, understanding hex nut sizes in the metric system is crucial for proper selection and use in engineering and manufacturing. The combination of various diameters, thicknesses, and strength grades allows for a tailored fit in countless applications. Always ensure to choose the right size and strength for your specific needs to guarantee a secure and efficient fastening solution.