Martelli's 18″ x 24″ cutting mat is made from durable, commercial-grade materials and features self-healing properties (with use of their ergonomic rotary cutters). It is also double-sided for color contrasting; one side is yellow (for darker materials) and one side is purple (for lighter materials).
The measurements are printed along the outside of the mat and along its center axes, so you'll no longer cover up numbers with your fabric or rulers. Mats also feature 45-degree and 60-degree angles, as well as concentric squares for squaring up your blocks.