Extension-style kits feature premium, brass cutter block with contoured edges to minimize gasket material buckling and assure precision cuts. Ergonomic design offers secure, comfortable grip. Easy-to-read, engraved, precision scale. Sliding, knurled nut adjusts cutting radius. Chrome-plated, steel extension bars provide for cuts up to 61" (1550mm) in diameter. Hex screws hold cutting blade for cuts up to ¾" (19.05mm) in depth. Includes rugged storage case, dove-tail designer template, bolt hole locator template, and center pin handle.