Passpartouts, also known as mat boards, are essential materials used for framing art pieces, photographs, and other flat objects. They come in different sizes, colors, and textures, making them versatile for various framing applications. Other synonyms for passpartouts include backing boards, mount boards, and mounting substrates. These materials provide support for art pieces and protect them from damage caused by moisture, dust, and insects. Other synonyms for passpartouts also include mounting boards, cut-out mats, and mounting cards. Regardless of the preferred term, these materials play a crucial role in the framing process, enhancing the display of art and photos for maximum aesthetics and preservation.