Hydro Crunch 1000W HPS MH Digital Dimmable Ballast for Grow Lights Internal rf protection Operates on AC 120V/240V ETL Listed and CE Certified with 2 years warranty Dimmable option: 400W/600W/1000W/Super Lumen Built-in cooling fan to run cooler than other digital ballasts Refer to the PDF attached below in Technical Specification for Installation manual.