A Hex Nut is a screw or a bolt with a threaded hole

A Hex Nut is a screw or a bolt with a threaded hole. These types of nuts are often used with mating bolts to secure parts together. They are a popular choice for securing bolts to a surface. They are available in a variety of sizes and can be used in a variety of applications.
There are three basic types of hex nuts: type I, type B, and type C. The type I is the most common and comes in a variety of sizes and material grades. It is best for applications that require high precision or frequent mounting. It can also be used on materials with minor surface roughness.
Steel hex nuts come in different strengths, or "grades." The cheapest ones are graded SAE 2 whereas the strongest ones are Grade 8 or Grade 304. The different grades are usually indicated by surface markings. The most common materials used to make hex nuts are steel, stainless steel, copper alloys, brass, and copper.
Heavy hex nuts made of AISI 316 grade stainless steel are available in ASTM A194 Grade 8M. The grade mark on these nuts indicates that they meet ASTM A194 Grade 8M requirements for high-temperature service. These nuts are often used with stud bolts.
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