The John Deere RE227949 is a genuine OEM 120V 1000W coolant heater designed to pre-warm engine coolant, ensuring easier cold-weather starts and reduced engine wear. This essential component is compatible with a wide range of John Deere agricultural and construction machinery, including numerous D, E, R, and S series tractors, combines, and R series sprayers. Weighing approximately 0.45 kg, it is a direct replacement for the original part, also superseding RE509531, providing reliable performance and fitment.