The sensing means includes a directing means for directing pressurized fluid to the second reaction chamber upon {HEAD ~ completion} of {TAIL ~ the dual modulated increases} in fluid pressure 
The sensing means includes a directing means for directing pressurized fluid to the second reaction chamber upon { HEAD ~ completion } of { TAIL ~ the dual modulated increases } in fluid pressure
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH