The Milwaukee 14-30-2805 Gear Box Impacting Assembly provides the internal gearing needed to transfer mechanical movement in compatible impact tools. The gear components work together to transmit rotational force through the tool during operation. This replacement assembly is designed to replace worn or damaged gearing during power tool maintenance or repair. Proper installation helps... https://www.wholetoolbox.com/milwaukee-14-30-2805-gear-box-impacting-assembly/14-30-2805.html