Columbian #9 Security Envelopes, 500/Box, Double Window, 3-7/8" x 8-7/8", Release & Seal Self Seal, SimplySafe Tamper Evident, White (COLO183)

Columbian #9 Double Window Envelopes are built for businesses that rely on accurate, professional business mailings every day. These white security envelopes work well for invoices, accounting documents, and sensitive client information, allowing only addresses to appear in the windows. The top window measures 7/8 x 3 1/2 inches, 3/8 inches from the left and 2 inches from the bottom. The bottom window is 1 x 4 inches, 3/8 inches from the left and a 1/2 inch from the bottom. To help protect sensitive financial information, each envelope features a blue security tint with a printed privacy pattern. This internal design limits visibility through the paper, reducing the risk of confidential data being read during handling, sorting, or delivery. Each envelope features a SimplySafe tamper-evident seal that clearly reveals if the envelope has been opened, helping protect sensitive contents from unauthorized access. The durable 24 lb white wove paper and side seams provide durability during mailing while maintaining a high-quality finish for both small offices and high-volume mailrooms. Mailing efficiency is improved with self seal business envelopes. The Release & Seal peel-and-press adhesive creates a strong seal without moisture, helping streamline workflows and keep hands, desks, and equipment clean. The adhesive remains protected until use, making these envelopes reliable even after extended storage. With 500 envelopes per box, this bulk pack supports consistent mailing needs without frequent restocking. Columbian Security Envelopes offer a smart solution for businesses that value privacy, efficiency, and a polished presentation in every mailing. (Manufacturer Item Number: COLO166)