$9.90 each when you buy a case of 500? That's amazingly cheap.
Amusingly enough, the brand name has been conspicuously censored in all the images, but I can make out the German(!?) text "2-Gang Handbohrmaschine" and a website "westfalia.de" --- which makes me wonder if they're making fakes of https://www.westfalia.de/shops/werkzeug/handwerkzeuge/bohren... (which sell for almost 3x as much) or are actually the OEM.
[1] https://www.alibaba.com/product-detail/Double-Pinion-Two-Spe...