What size Portfolio Case will accommodate A0 boards?

A0 paper is comparable to US size 33 x 47 inches, therefore the 36” x 48″ case is suitable. A1 paper is comparable to US size 24 x 33 inches, therefore the 24” x 36″ case is the correct size. A2 paper is comparable to US size 17 x 24 inches, therefore the 18” x 24″ portfolio case is appropriate.