Every long-haul economy seat comes with the same little kit: mask, socks, earplugs, a toothbrush the size of a fingernail. Most people wear the mask because it's there, push it up onto their forehead within an hour, and wonder why they land feeling like they didn't sleep at all. Used properly, it's doing far more work than "blocks the movie screen next to you."
Light is the master switch for jet lag
Jet lag is fundamentally a light-timing problem: your body clock is still set to the light-dark pattern of the place you left, and resetting it depends heavily on controlling when you're exposed to light in the new timezone. On the plane itself, cabin lighting, other passengers' screens and window light all send signals that can work against the sleep window you're trying to protect — especially on daytime flights or when crossing many time zones.
How to actually use it
Put it on before you try to sleep, not after you've given up. Decide your sleep window based on the destination timezone (not the one you left), and commit to darkness for that window rather than reacting to tiredness whenever it hits.
Fit matters more on a plane than at home. An upright seat, a headrest, and hours of wear expose every flaw in a cheap flat mask — pressure on the eyes, gaps that let cabin light in, an elastic strap that flattens the back of your head against the seat. A contoured design that sits off the eyelids and a soft strap make a genuine difference over an 8+ hour flight; it's the specific brief behind the Halo Zero Pressure Sleep Mask.
Pair it with the other levers. Hydration, avoiding alcohol (it fragments sleep and dehydrates you further at altitude), and getting daylight exposure at the right time on arrival all matter alongside the mask — darkness on the plane sets up the reset; light exposure on the ground finishes it.
The honest bit
A mask won't erase a 15-hour time difference in one sleep, and it won't help if you're too uncomfortable to sleep for other reasons — a genuinely upright seat and cheap earplugs solve different problems. It's one lever among several, but it's the cheapest and most controllable one you carry on board yourself.
The one-line version
Decide your sleep window by the destination clock, mask up before you're desperate, and let daylight do the rest once you land.
