The ballast, capacitor, and igniter in the Amazon description refers to using the LED lamp to replace a sodium vapour bulb, usually in a large, outdoor lighting fixture, like a street lamp. The LED doesn&#x27;t need the same support electronics that are required to warm up, start, and control sodium vapour lamps, which have a negative resistance once they get going, and thus will burn out quickly without a ballast in the circuit.<p>The LED lamp has just as much (or more!) support circuitry, but it&#x27;s built-in; note the comment in one of the reviews that it takes about four seconds to light up once power is applied.