Patent ID: 8726595

Claim:
A surface covering comprising: a plurality of building units, each having a plurality of nonlinear mating sides and a plurality of non-mating corners disposed alternatively on an outer contour surface, each non-mating corner being generally rounded, wherein mating of the plurality of building units forms the surface covering, and wherein the surface covering has a plurality of openings, each surrounded by the non-mating corners; and at least a first mating side of each of the building units intersects with a major axis, and at least a second mating side of each of the building units intersects with a minor axis, wherein the major axis and the minor axis are generally perpendicular and meet at substantially the center of the building units and the units have a dimension along the major axis that is longer than the dimension of the unit along the minor axis, wherein each of the mating sides is a centered rotation about the respective axis that the mating side intersects with, each of the mating sides having substantially the same length and configuration such that all of the mating sides of one unit are capable of mating any mating side of another unit.