According to {TAIL ~ one embodiment} of the invention, {HEAD ~ the pockets} are defined by upstanding walls in the movable element adjacent the surface exposed to gases of combustion 
According to
According to { TAIL ~ one embodiment } of the invention , { HEAD ~ the pockets } are defined by upstanding walls in the movable element adjacent the surface exposed to gases of combustion
REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH