Alvin Isometric Paper is 20# basis, acid-free, versatile layout bond, printed with a non-reproducible blue grid on one side. Smooth, opaque surface suitable for pencil or ink. Ideal for mechanical drawing or design needs, especially machine design, architecture and patent office drafting. Isometric grid of evenly spaced lines at 30°, 90° and 120°, for drawing 3-dimensional objects rotated at 45°. Laser, copier and inkjet compatible.