Philips Flat Head Drywall Screw Half Thread

The main purpose of screws is to make industrial products form a fixed whole. In use, it often happens that the teeth cannot be closely connected with each other, the screw head breaks if the screws are locked too hard, or the teeth cannot be locked tightly due to poor tooth patterns, which is a problem of accuracy. Screws are "mass products", not handmade works of art. In mass production, they are supplied to consumers for the purpose of achieving high precision, stable quality and popular price.

Screws and screw rods are different from each other. Screws are generally called wood screws; It is the kind with sharp head at the front end, with large screw pitch. It is generally used to fasten wooden and plastic parts. The screw rod is a machine screw (mechanical screw), which is the flat head type at the front end. The screw pitch is small and uniform. It is generally used to fasten metal and machine parts.