Abstract: Coupling apparatus for releasably interconnecting cargo pallets to form trains thereof for transporting exceptionally long cargo usually co-mingled with cargo of more normal dimension. Such apparatus is operative to preserve the trainlike arrangement of such pallets, one to another, throughout movement over, and transfer between, various conveying apparatuses customarily employed for the handling of said pallets even though the apparatuses may be misaligned, one to the other, either laterally, vertically or angularly or combinations thereof. The coupling apparatus is particularly adaptable to pallets framed by extruded members having a plurality of spaced apart symmetrically distributed recesses formed therein and, in coacting relationship with alternate recesses, a plurality of hingedly mounted securing rings.