Poly binding covers (also called polycovers) are made from durable polypropylene, and are most often used as a back cover on bound documents. Because they are made of sturdy, opaque plastic, these covers are also frequently used on legal or financial documents. They are available in a number of colors, opacities, thicknesses, and textures, including decorative finishes such as diamond plate and hologram.
There are six, distinct poly cover finishes available: crystal, grain, hologram, leather, stripe, and sand. The most popular texture is leather, which is offered in two thicknesses (16mil and 20mil), a plethora of creative colors, and features a glossy finish similar to that of treated leather. Crystal texture covers are made of 16mil, translucent polypropylene, and have a diamond plate finish. Hologram covers are semi-transparent, with a reflective, holographic finish in a 16mil thickness. Grain texture covers are opaque with a medium texture, satin finish, and are available in a robust, 19mil thickness. Sand texture covers are opaque with a fine texture, satin finish, and come in a 12mil thickness. Striped covers are translucent, featuring a fine, grooved texture in a 12mil thickness.