Constructing overpasses, tunnels, storage sheds, and dozens of other structures now is simplified and fasten than ever! The zipper truck system is extraordinary machine that works very fast actually a 1.5 m of arch is constructed every 5 minutes. This system was developed by Lock-Block Ltd., Arch-Lock  which gives unparalleled geometric fit and tolerances, eliminating the need for mortar.    The video bellow will clarify all the doubts this construction system offers and its fast and easy work.

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