To provide a tightening device like a vice, which can prevent chips, cooling lubricant, and other pollutants from ingressing in fixing recessed parts not in use, and bored thread grooves, in a simple manner.
This tightening device is provided with a main body 1 roughly in a U-shape in cross section, a plurality of fixing recessed parts 8a, 8b and 8c or 9a, 9b and 9c, which are arranged in the longitudinal direction at intervals in such a way that one center is mutually faced to the other center for the selective engagement of fixing projections corresponding to jaw parts 11 and 12 which can be moved within the main body by means of screws and spindles, and can adjust the position upward, and with at least one slide 3 or 4 having a plurality of thread grooves for fixing screws for the jaw parts.