This is a gear puller that pulls out gear bearings, pulleys, etc.The 3-prong gear puller has less rattling and excellent workability.Range of Use (Outer Diameter): 0 - 3.9 inches (0 - 100 mm); Reach: 4.0 inches (102 mm); Number of nails: 3 pieces; Tools: 0.6 inch (16 mm) wrench; Material: Carbon steel