An apparatus includes a wall defining an opening. A first bracket is connected to the wall and defines a first channel. A second bracket is located across the wall opening from the first bracket and defines a second channel. A hinge connects the second bracket to the wall such that the second bracket can pivot from a first position in which the second channel is open toward the wall opening to a second position in which the second channel is open toward the first channel. The brackets are configured to retain the lens in an installed position in which the lens extends across the wall opening, the first bracket captures a first end of the lens, the second bracket is in its second position, and the second channel captures a second end of the lens.
