#10 business envelopes with self seal closure for convenience in standard business mailings! Your business is too important to leave the details up to chance. What are your needs when it comes to envelopes? Quality, convenience, privacy? Redi-Seal® closure requires no moisture, extends shelf life and provides a secure seal. 24-lb bright white stock gives mailings a professional look. Address Window. Seam Type: Diagonal; Flap Type: Commercial; Trade Size: #10; Security Tinted: No.