The $40 sleep mask that fixed jet lag and red-eye sleep for half of founder Twitter.
Manta solved a problem that every other sleep mask ignored: total light blockout without pressing on your eyeballs. The eye cups are adjustable and sit in front of the lashes, not on them. After 6 hours on a flight or in a too-bright room, you actually want to wear it again.
The PRO version adds eye-cup variants for different face shapes and a slightly upgraded strap that doesn't migrate. The price stayed under $50 because the core product was already nailed.
Where this falls in the longevity stack: it's the cheapest, most boring item on this list, and probably the one with the best ROI per dollar. If you travel frequently, sleep next to a partner with different schedules, or live somewhere with light pollution, you'll wear this every night.
Frequent travelers, anyone with light pollution, partners on different schedules, side-sleepers who hate flat masks pressing on their eyes.
You sleep in a perfectly dark room and never travel — the cheaper Manta Original ($25) does the job.