Columbian #9 Security Envelopes are ideal for mailing important documents or sending sensitive client information and are often used as reply or return envelopes for invoices and business mailings. Each security tinted envelope has a scrambled blue pattern printed on the interior that conceals the contents. These self seal envelopes have a special Redi-Seal closure that doesn't require any moisture to seal. Simply press the bottom flap to the top flap and close. Double window envelopes show sender and receiver addresses; the top window dimensions are 1-3/16 x 3-1/2 inches, 3/8 inches from the left and 2 inches from the bottom; the bottom window dimensions are 1 x 4 inches, 3/8 inch from the left and a 1/2 inch from the bottom. 24 lb White wove paper with side seams give these business envelopes a professional appearance. Stock up on number 9 mailing envelopes with security tint for billing paperwork, tax documents, accounting records and more. Overall envelope dimensions are 3-7/8 x 8-7/8 inches. White. Box of 500.