Sold as 500/Box. Envelopes are great for mailing letters and documents. Security tinted pattern helps to discourage reading sensitive information through the outside of the envelope. Made in the USA. Made from 24 lbs. white paper for durability. Convenient box of 500 envelopes ensures ample supply. These envelopes measure 4 1/8' x 9 1/2' in size, providing enough space for your mail. Simply position the address to show through the single-left window. Redi-Seal closure with commercial flap seals securely without moistening. Double-flap design keeps gum from sticking before use.