Black 13"x19" or 11"x17" engineered wood frame with plexiglass, or smaller 8"x12" thin-frame (plastic) plexiglass - perfect for our rectangular pieces that don't quite fit in the squares shown on the main home page. Your choice of paper. 13"x19" may be matted to 11"x17", 11"x17" may be matted to 8"x12" and 8"x12" may be matted to 5.5"x7.5".