07040603 is referenced by 15 patents and cites 6 patents.

The present invention is a set of at least three interlocking blocks where two of the blocks are set on a ground surface and are connected at their top surfaces by a particular configuration of the underside of the third block. Four square and raised parts with four key recesses are formed on the top side of the entirely plastic and unitarily molded block to mate with a cavity and four flanged posts on the underside of another identical block. The critical part of this invention is providing four key recesses in the raised part of the block into which interlock the flanged posts of the underside of the block.

Title
Leveler interlocking blocks
Application Number
10/431040
Publication Number
7040603 (B1)
Application Date
May 8, 2003
Publication Date
May 9, 2006
Inventor
Lo Yun Tai
Hong Kong
HK
IPC
E02C 3/00
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