The cutter chamber of 1PSS quadruple-shaft (shear) shredders are composed of double auxiliary shafts at the upper layer and double main shafts at the lower layer. Auxiliary cutter rings at the upper layer are functioning in forcible feeding, which could increase the output of the main cutter rings. Meanwhile, materials of big sizes are brought back to shredding chamber to be shredded repeatedly, so as to achieve the purpose of controlling the size of materials to be discharged. Main cutter rings at the lower layer have special shape which combines the technology of chopping and shearing, so that it achieves the purpose of shattering and volume reduction by shearing, crushing, tearing, puncturing, and hacking, etc. The quadruple-shaft (shear) shredder is the key equipment to achieve highly efficient and uniform shredding of various kinds of solid waste.