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Upgrade Your Sleep System With Sea to Summit Bag Liners

Liners can make your nights in a sleeping bag softer, cleaner, and either warmer or cooler. Find the shape and style to match your needs and improve the way you sleep outside or on the road.

Sea to Summit Reactor Liner inside tent sleep system(Photo/Sea to Summit)
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Whether you need more warmth from your sleeping mat and bag or staying dry is your priority, a sleeping bag liner can help. A liner can even give your old sleeping bag new life with a softer feel and cut down on fighting against the swishing fabrics of a bag as you turn over at night.

Different liner fabrics offer different performance benefits. Sea to Summit liners include materials like Thermolite, Coolmax, Tencel, and silk, all of which can add comfort and performance by adding warmth or wicking moisture.

Sleeping bag liners also act as a next-to-skin layer for your sleep system, as most liners are made from fabrics that stretch, and are soft against the skin. They also protect your bag from rubbing against dirt, skin oils, or campfire smoke in your clothes.

Additionally, it’s much easier to wash a liner after a camping trip than an entire sleeping bag. Just toss it in the laundry, and you’re good to go for your next adventure!

Sleeping bag liners add versatility to your backpacking and camping sleep systems.
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Sea to Summit Sleep Liners

New for 2024, the brand’s mummy-shaped technical liners have openings in the shoulders and a drawcord in the foot section. These are made to work with the Free-Flow zipper system used in Sea to Summit sleeping bags. The Free-Flow system includes a short side zipper and a footbox zipper that are secondary to the main full-length side zipper.

These openings make it easy to reach your arms outside a bag yet keep your core warm, which is useful when you’re getting ready for bed or just enjoying your morning coffee. The shoulder opening also acts as another venting option.

Sea to Summit makes liners to fit most needs. Most of the liners are available in a mummy silhouette, though there are rectangular shapes, too. They all come with a bio-based treatment that fights odor-causing compounds and are covered by Sea to Summit’s guarantee.

Check out some of Sea to Summit’s sleeping bag liners below! Additionally, Sea to Summit sleep systems are on sale through May 20. It’s a stacking sale, meaning the percentage marked down increases with every sleep system item purchased for a max of 25% when buying four items. That’s a lot of $$$ — and ZZZs!

Reactor Liner

Sea to Summit Reactor

One of the brand’s Thermal Boost Liners, the Reactor Liner adds warmth to your sleep system. It uses Thermolite Pro technology which includes heat-trapping knit fabrics with hollow-core fibers and infrared-absorbing ceramic pigments that reflect your body’s heat. The knitted construction means the liner stretches and moves with you in your sleep.

The Reactor comes in a classic mummy shape or as a mummy with a drawcord footbox. That open footbox lets you hitch up the bottom of the bag and walk freely around camp — or to the bathroom. The mummy liner fits inside your rectangular-shaped bag.

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Reactor Extreme Liner

Sea to Summit Reactor Extreme Liner

This stepped-up version of the Reactor Liner is made for the coldest conditions. This slightly thicker liner adds almost 3 ounces of the same knit fabric with Thermolite Pro technology found in the Reactor. The hollow-core fibers and infrared-absorbing ceramic pigments still help retain your body’s heat while your bag retains the rest.

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Breeze Liner

Sea to Summit Breeze Sleeping Bag Liner Rectangular With Pillow Sleeve

For warmer conditions, the Breeze uses Coolmax fabric technology to help you stay dry and comfortable by wicking moisture from the skin while you sleep (or lounge). The knitted fabric blend includes Tencel Lyocell for a softer feel against your skin. That’s especially nice if you wear minimal clothing to stay cool during your slumber.

The rectangular liner has a standard-size pillow sleeve to house pillows you’d find in a hostel or hotel. The mummy-shaped version has the drawcord footbox mentioned above.

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Sea to Summit: Added Sleep Quality

Campers and travelers demand a lot out of their sleeping kit! That’s because they’re often exposed to the elements, so a sleep system has to quite literally bring the heat — and comfort! Sleeping bag liners not only make sleep systems warmer or cooler, but they are also stretchier and softer.

If you toss and turn at night, you may benefit from having a layer that moves with you rather than swishing around against a sleeping bag’s fabrics. Additionally, travelers often use liners in hotels or hostels to put a little space between themselves and the sheets and pillows provided.

But no matter what your sleep system needs are, consider adding a liner to the mix to boost overall sleep quality. And if you’re looking for a new bag or pad, Sea to Summit makes those, too.

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Sea to Summit open drawcord footbox
Sleep liners add versatility to your backpacking and camping sleep systems.

This article is sponsored by Sea to Summit. Learn more about its sleep liners and other sleep system components.

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