Patent ID: 7984569

Claim:
A sole assembly comprising: a sole unit and a sole unit receiver; the sole unit receiver having a thin cavity defined by a top surface and a downwardly extending sidewall that is disposed along a perimeter portion of the top surface, and the sole unit sized to substantially fill the cavity; the sole unit having one or more engageable elements, the sole unit and engageable elements being adapted to be received by the sole unit receiver for an item of footwear to form a sole unit assembly, the one or more engageable elements each having a corresponding engageable element on the sole unit receiver to form a male-female pair of elements that provides an interference fit that helps secure the sole unit to the sole unit receiver relative to forces that may act generally parallel to the ground facing surface of the sole unit; wherein the interference fit is in the nature of a bidirectional stop that helps secure the sole unit against forces that act generally along at least a long axis of the sole unit; wherein one of the pair of engageable elements of the sole assembly is a male part having an elongate portion that is generally oriented perpendicularly to the ground facing surface of the sole assembly; the end of the male part that engages the complementary female part terminates in a shape that has an outwardly extending horizontal component that resists vertical forces; wherein the horizontal component extends gradually and radially from the elongated portion of the male part; wherein the male part extends from the sole unit in a midfoot portion; and wherein one part of the male-female pair of engageable elements comprises a material of a relatively higher durometer than that of the other part.