An auto-feed paper shredder operates by using counter-rotating belts to grasp sheets of paper from the bottom of a stack of paper and push the sheet into a shredding mechanism. Successive sheets are pulled from the stack and shredded so that an entire stack of several hundred sheets can be shredded without operator intervention. The belts that accomplish the auto-feeding are housed in roller belt assemblies that can be easily removed from and reinserted into the paper shredder. In this way when the belts become worn and no longer effectively grasp the paper, the user simply removes the assembly and inserts a new one. The worn assemblies can be returned to the manufacturer to be refurbished.