These 30 sheet pads feature beefy 100lb (163 gram) multi-purpose paper for use with dry media such as charcoal, pastel, pencil and Conte and other drawing crayons.They work well with pen and ink including the Pitt pens and Sakura Pigma pens too.Pads are micro perfed to tear out easily and are 1/2" larger on the tear out side so they fit a standard frame. For instance the 9.5x12" taken out of the pad measures 9x12". Two smaller sizes are side spiral bound, large size is top spiral bound.