ASTM F912 Hex Socket Set Screws are a headless fastener threaded its entire length (except for the point) used commonly for fastening mated parts such as a shaft and collar. The F912 specification covers the requirements for quenched and tempered alloy steel socket set screws. Dimensional specifications are governed by ASME B18.3. These set screws are intended for compression applications only and are not customarily subjected to embrittlement tests. The socket set screw's headless design allows the fastener to sit flush, or inset, into the threaded part.