{HEAD ~ The piston head} is fitted into a cylinder which divides {TAIL ~ the cylinder} into two hydraulic or pneumatic cells 
{ HEAD ~ The piston head } is fitted into a cylinder which divides { TAIL ~ the cylinder } into two hydraulic or pneumatic cells
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH