Swingline SmartCut 18 Inch Replacement Cutting Mat for Commercial Series, 2 per Pack, Gray (9618CM) Replacement 18 - Inch cutting mats 2 mats per pack Each cutting mat has four cutting surfaces and should be replaced when worn Self-healing for long-lasting durability Designed to fit the Swingline SmartCut Commercial 18 - Inch Heavy Duty Rotary Trimmer or the GBC A520Pro Rotary Trimmer (sold separately)