The Hydro-Gear ZU-KEEE-5L7C-3UXXHYD is a genuine OEM ZT-3400 integrated hydrostatic transaxle designed for commercial zero-turn mowers that require outstanding durability, torque capacity, and smooth hydrostatic operation. Built with Hydro-Gear's commercial-duty design, the ZT-3400 combines a high-efficiency axial piston pump and motor with an integrated charge pump, heavy-duty gearing, and an external oil filter to provide reliable performance in demanding mowing applications. Manufactured to original equipment specifications, it restores original factory performance and reliability.