This essentials volume is dedicated to the development and effectiveness analysis of an innovative planetary gearbox design, taking into account fundamental engineering requirements. A James-type planetary gearbox of the “2K‑H” configuration was further developed, manufactured, and tested using double radial planet gears to achieve a more efficient drive for a ball mill used in cement production. The resulting gearbox is smaller, lighter, and exhibits a higher critical rotational speed than the original design. The work also examines, among other aspects, the selection of optimal gearbox parameters, vibration resistance, and the economic feasibility of the further development.