Come and Check Our Promo Solutions.Thickness upgrade (0.18mm) - our reusable envelopes are thicker and more durable than other polyethylene envelopes on the market, protecting your paper from damage.The envelopes are acid free waterproof.Transparent file folders, with various colors and visible contents, can easily find files without opening the envelope.The unique label bag design helps to easily classify and identify documents. Pls check inventory and detailed info with us before placing your orders.