Strathmore 400 Series Toned Mixed Media 18 x 24" pad 184lb (300 gsm) Vellum Surface Black. Suitable for - colored pencils, pastel, charcoal, pen and ink, watercolor, gouache, acrylic, graphite. Acid Free Paper, 100% Recycled with 30% Post Consumer fiber. Ideal for Finished Artwork with Flip over Cover Features sheets.