Dual Ferrite Smart Volt power cords are used with our ultra low RFI emission Grow Amp? ballasts. These dual ferrite noise dampening cords may be used with other products, dampening ability will vary based on ballast used. Sunlight Supply? makes no claims of ballast compliance if this cord is used with any other brand electronic ballast. Cords are 6.5 feet long. Choose from 120 volt or 240 volt.