(under subclass 257.1) Structures in which adjacent walls are joined at their meeting edges by rigid interlocking means, such as dovetailed tongue-and-groove or plural stud-and-keyhole parts, which are either integral with or rigidly secured to, said walls in more than one direction.
SEE OR SEARCH THIS CLASS, SUBCLASS:
265.5, for knockdown cabinets having adjacent sidewalls adapted to connect but not interlock.
