VIVOSUN 1000 Watt UL listed Dimmable Electronic Digital Ballast for MH HPS Grow Light Bulb Lamp 1000W Dimmable Ballast: Dimmable level: 600w; 750w; 1000w; super lumens (110%) Operates on 120/240V, 50/60Hz power supply. 8ft 120V power cord included. Strike both MH and HPS bulbs. Overheating Protection; End-of-Bulb-Life Protection; Short Circuit Protection; Ignition Failure Protection. Note: Ballast should be the same watts as the bulb, or it may blow your bulbs. The extra setting is to adjust the brightness (lumen) of the bulb. Different lumens have different effect on the plants. What You Get: VIVOSUN ultra bright 1000w digital ballast, 8ft 120 volt power cord, four rubber feet, UL certified guarantee, our fan-favorite 3-year warranty and friendly customer service.