![Amazon.com : TOPHORT 400 Watts Digital Dimmable Electronic Ballast for HPS MH Grow Light Bulb Lamp (400W, Blue) : Patio, Lawn & Garden Amazon.com : TOPHORT 400 Watts Digital Dimmable Electronic Ballast for HPS MH Grow Light Bulb Lamp (400W, Blue) : Patio, Lawn & Garden](https://m.media-amazon.com/images/W/IMAGERENDERING_521856-T1/images/I/51HN+-IDy2L._AC_.jpg)
Amazon.com : TOPHORT 400 Watts Digital Dimmable Electronic Ballast for HPS MH Grow Light Bulb Lamp (400W, Blue) : Patio, Lawn & Garden
![Hydro Crunch 400-Watt Digital Dimmable Ballast 120/240-Volt for Grow Lights C02A011050 - The Home Depot Hydro Crunch 400-Watt Digital Dimmable Ballast 120/240-Volt for Grow Lights C02A011050 - The Home Depot](https://images.thdstatic.com/productImages/1a46c9a6-5730-465b-86dc-5e8083257bda/svn/hydro-crunch-grow-light-kits-c02a011050-64_600.jpg)
Hydro Crunch 400-Watt Digital Dimmable Ballast 120/240-Volt for Grow Lights C02A011050 - The Home Depot
![Universal Core and Coil Ballast Kit For 400W Metal Halide Lamp 120V to 480V | P400ML5AC4M500K | Bulbs.com Universal Core and Coil Ballast Kit For 400W Metal Halide Lamp 120V to 480V | P400ML5AC4M500K | Bulbs.com](https://www.bulbs.com/Images/productmed/1/12562.jpg)
Universal Core and Coil Ballast Kit For 400W Metal Halide Lamp 120V to 480V | P400ML5AC4M500K | Bulbs.com
![Universal Core and Coil Ballast Kit for 400W Metal Halide Lamp 120V to 480V | M400ML5AC4M500K | Bulbs.com Universal Core and Coil Ballast Kit for 400W Metal Halide Lamp 120V to 480V | M400ML5AC4M500K | Bulbs.com](https://www.bulbs.com/Images/productmed/1/12513.jpg)