Our #9 Double-Window Envelopes are specifically designed for the secure mailing of business and legal correspondence, invoices, and other confidential documents. The interior of each envelope features a privacy-tinted pattern, engineered to provide comprehensive protection for your sensitive data. With their internal privacy tinting and secure lining, these envelopes ensure that the contents of your invoices and bills remain shielded from prying eyes-even under bright lighting conditions-giving you complete peace of mind when mailing. This design makes sending invoices in bulk faster and simpler than ever: simply peel off the adhesive backing and press to seal-no glue sticks or envelope licking required-saving you valuable time. It is the ideal choice for high-volume bulk mailings. Each box contains 500 high-quality #9 double-window envelopes, providing ample supply to meet your large-scale mailing requirements. Weight: 5.68 lbs.