Quality Park 9 x 12 Treated, Security Tinted Catalog Envelopes with Redi-Strip® Closure - Catalog - 9" Width x 12" Length - 28 lb - Flap - 100 / Box - White Catalog envelopes are made with a material that inhibits the growth of mold and mildew to protect the product. Redi-Strip on the flap provides a clean, quick seal immediately upon contact. Simply peel off the adhesive strip and press to seal. The peel-off strip protects the adhesive from dust for a longer shelf life. Envelopes are tinted to protect the privacy of your contents.