Metric socket set screws are headless and are threaded over their entire length. There is a hex or square-shaped socket at the top of the drive in place of a head. Metric socket set screws come with either cup or knurl cup points shaped to bear on a mating part. The fact that the metric socket set screw is without head allows it to go in flush.

Metric socket set screws are often found in electronics, in pulleys and shafts, and other places where flush mounting and space are important concerns. They are also used for internal wrenching and where frequent disassembly or adjustment occurs.