An accessory part for a medical device, such as an operating table or a transport board. Accessory devices may include a first plate for supporting a patient, and a second plate which can be moved relative to the first plate within a predetermined adjustment range. Devices may include a first clamping surface and a second clamping surface at a distance from the first clamping surface, wherein movement of the second plate relative to the first plate causes movement of the second clamping surface relative to the first clamping surface in a direction substantially parallel to a surface of the first or second plate, in order to increase or reduce a clamping force between the accessory part and a suitable holder on the medical device. Methods and medical devices for use with the accessory parts are also disclosed.
