A system includes a plurality of connected frame units. Each frame unit includes a first end plate connected to a first end of a frame element, and a second end plate connected to a second end of the frame element. The plurality of frame units is movable between a first state and a second state. In the first state, the plurality of frame units has a first width along a width axis of the plurality of frame units, and a first frame unit and a second frame unit of the plurality overlap by a first overlap amount along the width axis. In the second state, the plurality of frame units has a second width along the width axis and the first frame unit and the second frame unit overlap by a second overlap amount along the width axis.