Sea to Summit Reactor Sleeping Bag Liner Extreme Standard | Warmth & Hygiene

Sea to Summit Reactor Sleeping Bag Liner, Extreme Standard

The Reactor sleeping bag liner from Sea to Summit adds a layer of warmth and personal hygiene to any sleeping bag. Sized Extreme Standard at 85 x 31.5 cm, this mummy‑shaped liner uses a stretchy knitted fabric to move with you, making it a versatile companion for a wide range of sleep setups while remaining compact for travel.

Key benefits

• Adds warmth without adding bulk, helping you adapt to cooler nights or damp environments.
• Thermolite Pro technology uses hollow-core fibers and infrared ceramic pigments to reflect heat back toward you for added warmth and comfort.
• Drawcord footbox can be opened or closed for personalized comfort and integrates with selective Sea to Summit Free-Flow Zip systems.
• HeiQ Fresh odor control helps keep the liner feeling fresh after extended use or multi-night trips.
• Knitted fabric offers excellent stretch, supporting freedom of movement and compatibility with bags of various shapes.
• Lifetime guarantee from Sea to Summit adds long‑term value and confidence in the liner’s durability.

How Thermolite Pro works

Thermolite Pro combines knitted hollow-core fibers with infrared ceramic pigments. This combination is designed to reflect your body heat back to you, creating a warmer feel under the same sleeping conditions. The result is a softer, breathable layer that complements a wide range of sleeping setups without locking you into a single bag style.

Fit, comfort, and compatibility

The Reactor liner is cut in a mummy shape but features a highly stretchable knit that moves with you. A drawcord footbox offers flexible comfort options, and the liner is designed to integrate smoothly with the footbox of Sea to Summit’s Free-Flow Zip system in select bags, helping you achieve a cleaner, more adaptable sleep system.

Odor control and freshness

HeiQ Fresh technology helps manage odors, supporting a fresh feel through extended use. This is particularly helpful when you’re on back‑to‑back trips or camping in humid climates where washing options are limited.

Durability and value

Durability is a focus in the Reactor liner, and Sea to Summit backs it with a lifetime guarantee. This emphasis on enduring quality may appeal to travelers who want a reliable warm layer that stands up to frequent use.

What this liner can do for you

• Offer an extra warmth option for chilly nights or damp environments.
• Help keep your sleeping surface cleaner between washes.
• Provide mobility within a mummy‑shaped design thanks to a stretch knit.
• Maintain freshness on longer trips with odor control technology.
• Pair with compatible Free-Flow Zip footboxes for a streamlined setup.

Ideal use scenarios

• Backcountry and campground nights where a lightweight warmth boost is useful.
• Trips spanning multiple nights with limited laundry options.
• Purchasing a versatile liner that works with sleeping bags of different shapes.
• Travelers seeking a durable, long‑term sleep system component.