Models G52SP and D52SP travel quickly and grind quickly, says the company. The boom design creates a 52-inch cutting arc, and a hexagon-shaped cutter wheel offers low resistance and friction through the stump. Six multi-tipped cutting tools are fastened with one bolt and deliver the grinding performance of 24 teeth, the company says. Powered by either a 27-hp Kohler gas or 34-hp Caterpillar diesel, the grinders have a top speed of 3.2 mph. Standard warranty is one year on the machine with an OEM warranty on the engine.