wherein said slide faces and piston shoes have a pair of extensions at opposite ends of said medial portions in {HEAD ~ the direction} of {TAIL ~ the movements} of said piston shoes, 
of
wherein said slide faces and piston shoes have a pair of extensions at opposite ends of said medial portions in { HEAD ~ the direction } of { TAIL ~ the movements } of said piston shoes ,
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH