Sleep is a keystone habit for high productivity. Getting enough sleep doesn’t by itself guarantee success, but a lack of sleep will definitely stack the deck against you.

Our circadian rhythms regulate our sleep cycle. When it gets dark, we get tired. When it gets light, it’s time to get up, so we wake up.

Sometimes, we need to sleep when there’s light around us. Shift workers need to sleep during the day. If you’re trying to sleep on a plane, or even in a strange hotel room, there’s light around you. And if you’re sick or have a newborn, you need to sleep any time you can.

The simplest way to reduce the amount of light hitting your eyes is with a sleep mask. Personally, I’ve never been a fan. They’re uncomfortable, ineffective, and half of them won’t even fit on my head.

A couple years ago, I heard the Manta Sleep Mask mentioned on The Productivity Show. It wasn’t just once. It came up again and again. They swore by it.

I was skeptical. I’d tried sleep masks before. They all have the same problems: they’re uncomfortable, ineffective, and barely fit.

The Manta Sleep Mask? It’s amazing. At $30 (affiliate link), it’s the most expensive sleep mask I’ve ever owned, but it’s also the best.

Soft, comfortable, and 100% machine-washable.

The point of a sleep mask is to keep out light so your brain thinks it’s nighttime and therefore time to sleep. If the material isn’t thick enough or light can leak in around the edges, it isn’t doing its job.

The material the Manta Sleep Mask is made from is thick. It doesn’t let light through. Someone could shine a flashlight in your face and you wouldn’t notice it. Even direct sunlight doesn’t make it through.

If light can’t make it through the mask, what about going around it? Thanks to how adjustable the mask is (more on that shortly), that’s probably not happening, either. Yes, you could lay on your side and really smash the mask to deform it enough to create a light leak around the edges, but you’ve almost got to do it on purpose.

I’ll put it this way: I’ve laid down to take a nap with the mask on, had my wife walk in and turn on the lights, then turned them off again when she saw I was trying to nap. The only way I knew the lights had turned on and off was by hearing the light switch.

You can position the soft eye cups wherever you need them.

Most sleep masks work by stretching a thin piece of fabric across your eyes. This has the unfortunate effect of putting pressure on your eyes. Not only is this uncomfortable, it deforms your eyeballs. Have you ever taken off a sleep mask and had to wait a few minutes before the world would come into focus again? That’s why.

The Manta Sleep Mask is completely adjustable. The eye cups are attached by velcro. You can position them exactly where they need to be for a perfect fit. Lay on your back, position the cups on your eyes so they’re comfortable, then lower the mask into place. The cups form a seal around your eyes that keeps out the light. All the pressure is on the eye cups, not your eyes. I can open my eyes with the mask on and blink without my lashes getting caught.

The Manta Sleep Mask will comfortably fit larger heads.

The last two sleep masks I bought had thin, flimsy straps. One of them barely reached all the way around my head; the other didn’t quite make it. The Manta Sleep Mask has a long strap with continuous Velcro that gives me plenty of room.

Plus, the Velcro isn’t the kind we all wanted on our sneakers in third grade. (No time for laces, I guess.) It’s a micro Velcro that feels almost smooth to the touch, but it sticks.

Put it all together and this is an incredibly good sleep mask. It’s comfortable, it does what it’s supposed to do, and it looks good doing it.

You can get the Manta Sleep Mask on Amazon (affiliate link) or directly from Manta Sleep.