Gamma Series — Available in both hardbound and wirebound formats, these sketchbooks contain 62 sheets of 100 lb (150 gsm), ivory paper with a vellum surface and a distinctive tooth. Ideal for dry media and light washes, the paper is both internally sized and surface-sized. The wirebound sketchbooks contain 50 sheets (100 pages) of paper.
--
Stillman & Birn Gamma Series Premium Sketchbooks