These envelopes are made of durable, yet pliable opaque plastic and features a secure, two button and string tie closure. Take advantage of this multicolored set by color categorizing your documents for better organization! Use these to organize your documents at the office or use them at school to organize your homework and arts and crafts work or even use it at home to separate your bills. Details: Assorted colors 5.25" x 7.5" Pack of 18 booklet envelopes Button string closure Plastic