To perform operation without holding a trunk part of a hold-press button slave machine with the palm.

When an attachment 1 is installed on the bed or the like and force is added to a surface part of an operation part 3, the operation part 3 is bent against the surface part. A lever part 8 provided on the reverse part of the operation part 3 is energized into the direction that a press button 12 is pressed. Thus, when the attachment 1 is fitted to the hold-press button slave machine 10, a patient can operate a press button 12 by hitting or pressing the operation part 3 with the palm or a fist in the same way that the hold-press button slave machine 10 is held with the palm to press the press button 12 with a thumb.