In the linear version, {TAIL ~ the power transfer shaft} is attached to {HEAD ~ a piston head} 
In the linear version , { TAIL ~ the power transfer shaft } is attached to { HEAD ~ a piston head }
OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD