· 3. EFCUT C30 Mini Wood Chipper Shredder Mulcher, 7 HP 212cc Gasoline Engine, 3" Max Wood Diameter, 15:1 Waste Reduction Ratio, 2Year Warranty After Product Registration. View on Amazon. SCORE. AI Score. The scores from 0 to 10 are automatically scored by our AI Consumer Report tool based upon the data collected.