a multi - layer sheet structure , in an exemplary embodiment , includes a first layer of a thermoplastic olefin composition that includes polypropylene and a filler , and a second layer that includes a polyolefin composition . the second layer positioned over at least a portion of the first layer . the multi - layer sheet structure also includes a third layer that includes an adhesive , and a fourth layer that includes a transparent acrylic composition . the third layer is between the second layer and the fourth layer .