This is the K'nex set that is "MarioKart Wii Mario vs. Chain Chomp" Building Set -- it is in the original box. There may be a piece or two missing from this set, so I am marking it as incomplete. I will continue to try and find other. pieces and edit if I can. The set is in very good condition. My son put it together and then didn't really play with it. Thank you for shopping!