Abstract: The present invention is related to spacers that can create fluid flow space at a variety of structural interfaces, particularly in building construction. The spacers of the present invention include unique hinges that can physically couple one panel of the spacer to another panel of the spacer in a manner that substantially distortionally separates the two panels. Preferred embodiments include a folded hinge having at least two folds. The spacers of the present invention also include unique panel dimples that help control the rigidity of the panel. In preferred embodiments, elongated dimples are used to help control rigidity.