Avery® Semi clear sheet protector made of non-stick economy weight propylene. Sheet protector supports sheets that measures 8 1/2″ x 11″ and offers secure storage and is semi-transparent to avoid direct exposure of documents, sold as 50 per box. Made of “non-stick” economy-weight polypropylene 50 sheet protectors per box Protects 8 1/2″ x 11″ insert sheets Thickness: Economy Semi-clear, polypropylene sheet protectors won’t lift print off inserts Inserts can be easily inserted from top—no need for hole punching Acid free and archival safe Top loading – easier to load Specifications table Attribute name Attribute value color & material Color Family The PRIMARY material that the item is made of. Polypropylene/PP True Color Acid content determines how long the paper or product will last before breaking down. The acid level is measured by the pH (potential of hydrogen) on a scale from 0 to 14. Acid Free (alkaline) paper has a higher pH (above 7), has a longer life expectancy, and is less likely to discolor and break down over time. Acid Free Anti-Glare 3 Protector Sheet Capacity Lightweight Transparency Level Water Resistant style Loading Style Sheet Protector additional details Next Day Delivery 50 Series or Collection 50 to 74