Smooth surface, natural white sheet, 70# (114gsm) heavyweight sketch paper is an excellent choice for pencil and ballpoint pens. Recommended for use with Prismacolor Illustration Markers. 50 sheets per double wire side bound pads. 5.5″ x 8.5″ size is landscape, 3.5″ x 5.5″ and 8.5″ x 11″ sizes are portrait style. Get the most out of your shelf space and double stack the 5.5″ x 8.5″ sketch book for a double facing!