These No. 10 business envelopes with Redi-Strip deliver dependable performance. They made with a material that inhibits the growth of mold & mildew to protect the product. Protect sensitive client information with a blue tint pattern that makes it impossible to see the details of the contents, even when held up to the light. Redi-Strip on the flap provides a clean, quick seal immediately upon contact. Simply peel off the adhesive strip & press to seal. The peel-off strip protects the adhesive from dust for a longer shelf life. The 24 lb. bright-white stock gives your mailings a professional look.