Durable 100% cotton twill. Convenient utility pocket with two 6 1/4” x 6 1/4” compartments to keep art supplies handy. Heavyweight material can withstand repeated washings. Standard size is 23½ x 24½ while the extra large size is 25½ x 36½. Extra large size is height adjustable and features a locking clasp mechanism. Both sizes feature convenient utility pockets and extra long ties.