Built with the same collection of innovative features as all AK series grinders, the AK 640 is a high-volume machine designed to produce hundreds of yards of finished material every day. The up-swing hammermill engineering converts more of your source stream into a very consistent, high-quality product, maximizing your revenue and profit. Organics, shingles, wood waste, drywall — build your business on the back of the AK 640.