Abstract: A panel joining system of the kind that comprises two rigid and preferably metal plates between which a suitable insulating fill material is inserted, and where the panels are arranged in flush formation to one another, and each one possesses a grooved inset with respect to the plane thereof at the end on one of its faces at least, for the purpose of inserting a join cover to conceal the connection between panels from the outside, and where each panel possesses also a second innermost slot or groove close by to the first such groove as described, for the purpose of housing a bolt head or nut whose function is to secure the join between panels and, if applicable, to attach them to a stationary anchorage.