D2 Drag Knife Knife Cutting attachment for CNC Routers 1/2in shank Maximum cutting depth: 1/4 in. (6.3mm) Minimum cut radius in materials thinner than 1/8 in. (3.1 mm): 1/8 .in (3.1mm) Minimum cut radius in materials over 1/8 in. (3.1mm) thick: equals material thickness