This is a set of two Muse PD Pad Sunflower Paper M sketchbooks. Each sketchbook originally had 15 sheets, but 2 sheets have been used, so one has 15 sheets and the other has 13 sheets. The paper thickness is 211g, and the top edge is glued. The size is B5. The "M" on the cover indicates "M drawing paper, extra thick." There is no yellowing or warping due to humidity.