It is an object of the invention to improve usability of a sander. The sander includes a rotary working surface (105), a driving mechanism that is disposed above the rotary working surface (105) in a direction of the rotation axis of the rotary working surface (105) and rotationally drives the rotary working surface (105), a cylindrical housing (103) that houses the driving mechanism, and a movable handle (117) that is mounted on a surface of a cylindrical part of the cylindrical housing (103). The movable handle (117) can be turned around the central axis of the cylindrical housing (103) and can be fixed at an arbitrary position in a circumferential direction of the cylindrical housing (103).
