Hand-tightening jigs are jigs for fixing a workpiece to a table or base jig of a machine tool by hand-tightening. This category includes clamping parts, clamping units and locating elements. Clamping parts are individual parts of jigs for hand tightening of workpieces and include screw jacks, toggle clamps, and T-slot nuts. Clamp units are jigs for fixing workpieces similar to clamping parts, but they are set consisting of various parts. Locating elements are tools and optional parts used for positioning and raising workpieces and supporting workpieces, such as guide blocks and straight pins.