1、 Concept

Standard parts: Refers to commonly used components that have been fully standardized in terms of structure, dimensions, drawing methods, markings, and other aspects, and are produced by professional factories, such as threaded parts, keys, pins, rolling bearings, and so on.

Fastener: A general term for a type of mechanical component used to fasten and connect two or more parts (or components) into a single unit. It is a standard component used for fastening and connecting purposes.

The characteristics of fasteners are a wide variety of specifications, diverse performance and applications, and a high degree of standardization, serialization, and universality. Therefore, some people also refer to a type of fastener that already has national standards as standard fasteners, or simply as standard fasteners. And others are called non-standard parts. But their important roles are the same.