GO! Rotary Cutting Mat-18" x 24" is a self-healing, double-sided, ultra-thick mat (3mm) and can be used with the GO! 45mm Rotary Cutter (55449) and GO! Quilting Ruler-6" x 24" (55474) for pre-cutting fabric strips for use with your AccuQuilt GO! Fabric Cutting System. The mat features gridlines with inch, 30°, 45° and 60° angle markings.