Versatile envelopes simplify your mailing and storage needs Ideal for sending flat, bulky materials or multiple small items, including coins, small parts and cards. Flap is located on the short side to help prevent items from falling out. Made of 80-lb paper. LUX Open-End Envelopes, 6in. x 9in., Smoke Gray, Pack Of 250 is one of many Coin & Mini Envelopes available through Office Depot. Made by LUX.