Use an Allen wrench (hex key) to secure with required torque as needed.
Although often used in machinery, they can be found around the home as well to secure window crank handles to window operators or to hold interior door knobs to spindles. Socket Set Screw 1/4in-20 X 5/16in Black Oxide Coated Steel 25PK Socket set cap screws have cup points that produce a thin edge that digs into hard surfaces for a secure hold.Size: 1/4 inch-20 X 5/16 inchHeadless screw that sits flush or below the surface once installedInternal socket drive requires Allen wrench (hex key) to installInstalls into an internally threaded hole to hold an object into placeOften used in machinery to secure gears to shaftsThread Type: Coarse, Thread Class: UNC-3A, Point Style: Cup PointSpecification(s) Met: ASME B18.3 & ASTM F912 This fastener is headless and contains an internal hex drive.