Seat Sack offers a Medium 15 Inch Storage Pocket that features a durable cotton and poly laminated fabric construction. It is flame-resistant and easy to clean with convenient machine washable materials. The Blue Seat Sack was created with a 10 inch deep and has a 2 inch gusset that offers ample storage space to accommodate books, papers, school supplies and more. Recommended for grades 2 to 3.