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Stainless steel screws and screws for great use

The types of screws, whether they are micro screws for glasses or large screws for large-scale heavy electrical engineering, have many types. The main purpose is to fix the height of industrial products into a fixed body. If there is often a lack of tightness between teeth during use, excessive force locking can cause the screw head to break, or poor tooth pattern locking cannot meet the usage conditions, all of which are quality and accuracy issues. Screws are "quantity products", not handmade artworks. In mass production, they aim to achieve high-precision and stable quality and provide consumers with affordable prices. The accuracy of screws is usually 6g level, while the rough screws used in construction projects are 8g level.

The main categories include ordinary screws, self tapping screws, and expansion screws.