a sheet of non reinforced thermoplastic material superposedly attached to said sheet of fiber reinforced thermoplastic material, wherein both of said sheets are jointly deformed substantially differently along different axes to form a cavity and wherein said sheet of fiber reinforced thermoplastic has {HEAD ~ a thickness} which varies over {TAIL ~ said cavity}, the thickness of the fiber reinforced thermoplastic being substantially thinner over said cavity than elsewhere 
varies over
a sheet of non reinforced thermoplastic material superposedly attached to said sheet of fiber reinforced thermoplastic material , wherein both of said sheets are jointly deformed substantially differently along different axes to form a cavity and wherein said sheet of fiber reinforced thermoplastic has { HEAD ~ a thickness } which varies over { TAIL ~ said cavity } , the thickness of the fiber reinforced thermoplastic being substantially thinner over said cavity than elsewhere
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH 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 OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH