Power Fist 8007177 is a maintenance kit for 4000 Ib capacity farm jacks. It consists of 2 Lifting Pins, 2 Lifting Pin Dowels, 2 Lifting Pin Springs, a Reversing Switch Spring, a Reversing Switch, and a Reversing Lever. The kit is used to replace worn or damaged parts on the jack, ensuring that it operates safely and efficiently. The kit includes all the necessary parts to perform the maintenance, and the instructions are clear and easy to follow.