Pan head screws include one slot and cross slot for choice. If using electric screwdriver for installation, the cross slot is generally selected. The materials of pan head screws are mostly iron and stainless steel, iron are low carbon, medium and high carbon steel, and the materials of stainless steel screws are stainless steel 201, stainless steel 304 and stainless steel 316.

Countersunk head screw, also known as flat machine screw, its head is a 90-degree cone, similar to common wood screws. On the surface of the mounting hole on the connector, a 90-degree conical socket is machined, and head of the countersunk head screw is in the socket and is flush with the surface of the connector.

Machine screws, also known as machine screws, are also one of the most commonly used fasteners. Machine screws are usually used alone (sometimes with washers), and generally play a fastening or tightening role.