Abstract: A zipper has its teeth formed by two interfitting plastic tooth elements one of which has pointed prongs fitting into matching holes in the other tooth element and extending through a fabric mounting strip having a bead clamped between the tooth elements of each zipper tooth. The tooth elements also interfit outwardly of the mounting strip by way of a land and matching recess, and an additional prong and matching hole. The interfitting tooth elements are welded together at the interfit of the prongs and of the land. The zipper is locked in closed position at each end by a locking unit which has a latch with locking pawls which fit between adjoining zipper teeth when the latch is swung into locking position after sliding the locking unit onto an end portion of the zipper.

Abstract: Flexible fabric barges are connected together in a string for towing. The barges are interconnected by fabric sleeves which have zipper connections. A fabric towing cone is zipper connected to the lead barge.