The Ampad Computation Book is ideal for scale drawings, drafting and planning, engineering and technical applications. Heavyweight 20 lb. ivory paper stands up to repeated use and causes less eye strain. Strong twin-wire binding holds together durable, red pressboard covers, allowing the notebook to lie flat. 76 Quad-ruled (4×4) sheets are sequentially numbered (1-152) for quick access to notes. 11-3/4″ x 9-1/4″ Size. 1 per pack.