➤ #10 SECURITY ENVELOPES. These 4 1/8" x 9 1/2" inch envelopes are designed with security print to protect contents and sensitive information, perfect for protecting sensitive information from others. ➤ SECURE. Just peel and seal to create a strong lasting seal without licking or moistening. Our self seal design is quick and easy and is guaranteed to stay sealed with no need for tape or glue sticks. ➤ WINDOWLESS DESIGN. Envelopes manufactured with a windowless front panel for easy printing, labeling or hand-addressing, perfect for quick, mass business mailings. ➤ WHITE 20LB STOCK. Perfect for everyday business use, these standard white envelopes are crafted of heavy, durable 20lb paper and securely holds hefty files during transit. ➤ MULTI-PURPOSE. These envelopes can easily fit invoices, letters, checks, gift cards, etc. These envelopes can be used for virtually anything you need them for!