Great for interoffice communication, the envelopes make it easy to pass documents between individuals without damaging the pages inside. The translucent cover allows the contents to be viewed from the outside, so the envelope can easily be identified. Poly XL Reusable Envelopes with a hook and loop closure are made from acid-free polypropylene. For 11 x 8 1/2 document storage. Side Loading. Sold individually in assorted Tropic Tones colors: Seaside Blue, Sunny Yellow, Seafoam Green, Sunset Red, Sandy Gray and Clear (no color choice).