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. In addition to countersunk head screws, there are also semi-circle head flat machine screws used in some occasions. This kind of screw is more beautiful and can be used in places where a little protrusion is allowed on the surface.
Flat countersunk head screws are an indispensable necessity in daily life or industrial manufacturing. According to various properties and functions, it is divided into countersunk head socket head cap screws, countersunk head slotted screws, etc.
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