JACs Circle Cutting Tool JAC's circle cutting tool is the perfect way to wrap around wiring harness circle from 25mm to 150mm.  Simply slide the blade to the desired size, the circular cutter around the material to card, after two corners and with the other hand turn the cutter serval by pressing the specified number holder.  The cutter is for use on card and paper up to 350 g/m².  Use with good quality cutting mat; for best results we recommend you use a glass cutting mat if available. Each circle cutter with blade, ready to use, with 3 additional blades, is located under one corner of the pad. Spare Blades come in a Pack of 6.