Re: What is this "box"
While todays technologies use semiconductors and PWM to fire a fluorescent lamp, they’ve traditionally been powered with a transformer based ballast. Placing this ballast in the handle of a fluorescent drop light added weight so until the newer technologies came along (and down in cost), it was placed in the cord near the plug or as a wall wart.
This is why we find newer fluorescent drop lights without a ballast in the cord but they can still be bought with them in the cord.
In the case of the OP’s drop light, it is surely a ballast for the fluorescent bulb.
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