A girth adjustable device for physical therapy such as the dilation and stretch of body orifices that can repeatedly, gradually increase a uniform and sustainable pressure over the entire lateral surface area and over the entire length of a body orifice at the same time, and gradually decrease the pressure uniformly from the entire lateral surface area and the entire length of a body orifice at the same time. The girth adjustable device comprises at least one controller, a housing, at least one threaded shaft, at least one module, a plurality of shaft member and at least one sheath. The part of the device inserted into a body orifice is the shaft. In a body orifice, the user via the controller rotates clockwise the threaded shaft to increase the girth of the shaft. Then, the user via the controller rotates counter-clockwise the threaded shaft to decrease the girth of the shaft.