The design blog Core77 shares this clever invention. The set (single?) of eyeglasses has a single lens that flips back and forth on a hinge. This feature allows a person to put on eye makeup while seeing clearly through the opposite-side eye.
The cosmetics and accessories store Donna May London offers them in seven different magnifications. It's the sort of unique, single-purpose tool like one might see on the subreddit /r/specializedtools.