Strathmore 400 Series Calligraphy paper is an acid free Thickness 20lb or 75 gsm, Size: 21.6 x 27.9 cm or 8.5'' x 11'', No. of Sheets: 50, natural white calligraphy paper that provides an ideal surface texture for smooth ink flow for lettering & calligraphy. The paper is 20lb or 75 gsm thick and works great with fountain pens . Crisp lines and almost no feathering