A PFO ballast is a core and coil ballast in a fancy aluminum enclosure, depending on the version required it has either a M59 or M58 ballast inside as well as others.
M59 is the ANSI for a 400 watt ballast, M58 is a 250 watt ballast.
Are you looking for an electronc ballst which is a whole different animal.
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-=Bryan=-
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