Patent ID: 7849655

Claim:
A panel comprising: a groove extending along a first edge of said panel, wherein said groove is defined between a first flange and a second flange, wherein the first flange extending along the first edge of the panel and protruding from a first side of the panel, wherein said first flange comprising a bottom surface extending parallel to the first side, and the second flange extending along the first edge of the panel and protruding from a second side of the panel opposite to the first side; a tongue extending along a second edge of said panel, wherein said tongue is on an opposing side of said first edge of said panel having said groove and said tongue is adapted to receive a groove of a similar panel so to mechanically lock together, wherein said tongue is configured in a S-shape, and said tongue has a lower surface extending between a bottom corner and a distal edge thereof, and a gap is defined between a back wall of the tongue and a separate side wall extending along the second edge of the panel; a shoulder defined by a consistent depth extending along a third edge, wherein said shoulder is adapted to receive a protruding lip of a similar panel; and a protruding lip extending along a fourth edge of said panel, wherein said protruding lip is located opposite of said edge having said shoulder, wherein when said panel is connected with a second panel having the same groove and tongue to form a mechanical lock, (i) void volume is created above the second flange, wherein said void volume created above the second flange comprises a first void volume above the second flange and below the lower surface of the tongue and a second void volume above the second flange and in the gap, and (ii) void volume is created below said second flange when forming the mechanical lock with the second panel.