Exercises In-Wall Loudspeakers Pr-Construction Bracket Instructions & Installation Guide This per-construction bracket kit will ald you in new construction installations of Polk Audi BC/ Se rigs Walloping-Ceiling Loudspeakers, This kit is also for use in installation situations in which the wall's utility to hold the weight of the speaker is questionable. These instructions are to be used in addition to your RCi Series owner's manual, Please read your manual carefully to avoid costly mistakes.