DISRAELI GEARS
Charger was a brand of derailleurs produced by Ko Shaing Industrial Co. of Taipei, Taiwan.
I believe that Ko Shaing Industrial Co. also manufactured the Lubao brand of, nearly identical, derailleurs. I have had it suggested to me that they may have started with the Lubao brand but then changed to Charger to make their products more saleable. Looking at the derailleurs themselves, I am not so sure about this. My guess is that they ran the two brands in parallel, perhaps for different markets. But this is all guesses layered on guesses.
Charger derailleurs were some of the first Taiwanese derailleurs that I ever came across. I have half a memory that one of the many struggling UK bicycle brand (Viscount?, Viking? Coventry Eagle? Elswick Hopper?) may have fitted them as a Shimano substitute at a point of financial distress. I remember being surprised that they seemed to be a accurately and strongly made and to be an acceptable substitute. Later Taiwanese copies of Shimano Tourneys seemed to be cheaper and tinnier than these early models.
Finally there is a history of Taiwanese derailleurs branded ‘KS’. I do not think that these have anything to do with Ko Shaing Industrial Co. - but they do share the same initials.