Shredders, sometimes referred to as "grinders, granulators", are different types of machines, these machines also chop up/reduce plastic, wood, paper, rubber and other waste, but in different ways. These machines utilize horizontal, single rotors with bolts, blades & knives to chop up the plastic, etc into manageable sizes - equipment does not pulverize the rubber or whatever is thrown in to the machine. Some of the shredders available include; Holtzmag, Linder, Weima. Single shaft is only one of a few different types of shredding systems, one example of another type is "dual/two shaft". Contact Davey Industries, some of the shredders for sale may not be listed on this website.