Xtrasun ballasts are engineered to provide reliable service at value prices. Designed in America and employing features and materials normally found on higher priced units, these have become the most popular value priced units on the market. Their unique patented aluminum housing with convection cooling runs so cool we offer a 5 year warranty - the longest in its class. Xtra Flexibility Use HALIDE for growing and SODIUM for flowering Xtra Versatile Works with most fixtures Xtra Value Super affordable UL Listed Ballast Size: 1000W, 600W - 5-3/4" x 7-3/4" x 13" 430W, 400W - 5-3/4" x 7-3/4" x 11-5/8"