Abstract: A device for axially clamping a rotary tool element fitted on a spindle of a power driven tool or the like includes a first flange and a second flange. The first flange is mounted on the spindle and has an inner part rotatable with the spindle and an outer part rotatable relative to the inner part about a longitudinal axis of the spindle through a bearing. The outer part includes a first surface for abutting on one end of the rotary tool element. An engaging mechanism is disposed between the inner part and the outer part for limiting rotation of the outer part relative to the inner part within a predetermined angle. The second flange is threadably engaged with a threaded portion of the spindle and includes a second surface for abutting on the other end of the rotary tool element. The second flange is operable to be tightened for clamping the rotary tool element between the second flange and the outer part of the first flange.