The Sun System Harvest Pro 600 watt magnetic high pressure sodium ballast features excellent grow light reliability and performance at a great price. Its aluminum enclosure is engineered to dissipate heat and keep critical components cool with separate compartments for the coil and capacitor. In the unlikely event a capacitor fails, you can easily change it out with Sun System's "EZ Cap Door." A heavy duty handle makes it easy to carry the ballast or hang it on a wall, while rubber feet reduce noise and vibration. The "Power Pointer" allows the ballast to operate on both 120 and 240 volt systems: Simply unplug the 120 volt power cord (included), turn the Power Pointer arrow down for 240 volt power, and plug in a 240 volt power cord (sold separately).