This disclosure relates to building trades where precise spacing between structural members ensures support via use of a plurality of elongate spacers. The spacers include at least one intermediate transit tacking member and a pair of nail- or screw-receiving apertures on opposing ends of thereof. One of the opposing ends serves as a pivoting end and the opposite end includes one or more relatively shorter member near the aperture formed therein. These member(s) can be driven into an adjacent trust or other support member while a final precise position is determined. To determine the final precise position to affix a given spacer one or more indicia is provided. Such indicia can include end edges, one or more cut-out features and/or one or more cut-out features and/or numbered or lettered (or other symbols) indicating the relative spacing from one end of the elongate spacer to the other.