US Patent 11523683 Blow-molded unitary structure with enhanced strength

A blow-molded unitary structure includes a panel having upper and lower panel surfaces and a ridge extending downward beyond the lower panel surface. The ridge includes a first side surface, a second side surface, and a lower ridge surface joined with the first side and second side surfaces of the ridge. The ridge further includes a plurality of depressions formed at one or more of the first side surface, second side surface and lower ridge surface. The plurality of depressions enhances the strength of the ridge, and the ridge in turn enhances the strength of the structure.