Yield Lab Horticulture 400w Dimmable Digital Ballast for HPS MH Grow Light SLIM LINE DESIGN: With its compact and light weight design, this ballast packs a punch. Able to run both HPS and MH bulbs, this ballast is your go to power supply for all of your hydroponic needs. With its large surface area and internal fans, this item will keep cool and avoid overheating. The ballast also runs completely silent so no more humming or additional noise. In the event of a shortage or power surge the ballast will also come with a spare fuse so you never have to compromise your grow SAFETY AND PROTECTION: Enjoy the peace of mind of a safe and certified product. With open circuit protection, short circuit protection, ignition failure protection, and over heat protection this ballast is built to last! Come see and experience the product that boasts UL and CE safety certifications and why many have made the switch to Yield Lab! ADJUSTABLE SUPER LUMEN BALLAST: Featuring Dimming Control you can effectively reduce lumen intensity as much as 50%. Utilize the Super Lumen Function to boost your output by 15% for later flowering stages. Experience the quality of industrial grade internal components that provide stead power, increased PAR, eliminates flicker and boost yields! INCLUDED COMPONENTS: 1x Yield Lab 400w Digital Dimmable ballast 120~240V (120V power chord included) INDUSTRY LEADING WARRANTY AND TOP CUSTOMER SERVICE: Manufactures warranty covers your ballast for 3 years. Lifetime support by phone and email and 100% Satisfaction Guarantee