WARNING: the space inside the frame is for the larger size on each selection, but you can mat the smaller size by taping it to the back of the mat. e.g., 13x19 frame with 11x17 mat has space that fits 13x19 picture exactly, and you can install an 11x17 picture by taping it to the back of the mat. Also note that the display area is always 0.5 inch smaller than your picture size. e.g., 13x19 frame with 11x17 mat has a display area of 12.5x18.5 for the frame and 10.5x16.5 for the mat. Wood MDF (Wood Composite) Material. All small frames have GLASS front face and back easel for placing the frame on a table top (This applies to 12x12, 11x14, 10x13,..., and smaller frames). All large frames have plexiglass/acrylic front face, NOT GLASS. Also, large frames do not have a back easel and can only be used on a wall (This applies to 11x17, 12x16, 12x18,..., and larger frames). For these large frames, please peel off the PROTECTIVE FILM from both sides of the plexiglass to reveal a clear view. All frames feature black backboards and back hooks for hanging frame (Landscape and Portrait) on a wall. Border width for all frames: 1 inch. Thickness for all frames: 0.6 inch. N.B: The frames will arrive fully assembled. Please hang these frames using the already installed back hooks. Do not hang by the frame border itself. A display picture is included as shown.