Abstract: A baffle tile that folds from a flat configuration into a three-dimensional configuration is disclosed. In the three-dimensional configuration, it includes a rim portion and a baffle portion. The rim portion is split into halves. Each half of the rim portion terminates in a pair of upwardly-folded, spaced-apart tabs. When the baffle tile is in its three-dimensional configuration, each tab meets and abuts its counterpart from the other half of the rim portion. Each tab has a notch in it, arranged such that the notches of abutted tabs are aligned. A retaining structure inserts into each set of aligned notches. The retaining structures prevent the tabs of the baffle tile from separating. In some cases, a single retaining structure that has approximately the same size as the baffle tile itself may also serve as a cap to enclose the tile.