Designed for fast-and-light adventures such as backpacking, cycle touring, and paddle touring, the Sea To Summit Reactor Lightweight Sleeping Bag Liner provides essential thermal boost without adding unnecessary bulk to your pack. Engineered with advanced Thermolite Pro fabric, this liner utilises hollow-core fibres blended with infrared-absorbing ceramic pigments to retain your body's radiated warmth, raising your sleep setup's temperature by up to 4°C (7°F). Its flexible stretch knit construction moves with you throughout the night, while integrated arm openings offer complete freedom of movement without compromising insulation.

Built with an ergonomic technical shape and a fitted hood, it easily fits any sleeping bag and connects seamlessly using built-in snap connectors to prevent twisting during sleep. It is also exceptional for travel hygiene: the quick-drying, easy to clean material is treated with HeiQ Fresh odour control to keep your bed fresh over long trips while reducing total laundry cycles for your primary bag.

Crafted from recycled fibres and bluesign approved materials, it compresses effortlessly into its included stuff sack, making it a sustainable and invaluable component for any backcountry sleep system.

Key Features:

  • Long Size: With a length of 206cm, recommended for users with a maximum height of 198cm.
  • Thermolite Pro Insulation: Advanced hollow-core fibres infused with infrared-absorbing ceramic pigments capture and bounce body heat back to the user, enhancing sleep setup warmth with minimal pack size.
  • Ergonomic Mobility: Made with a stretch knit textile and flexible arm openings that allow natural movement for comfortable, unrestricted sleep.
  • Anatomic Design: Features a technical shape alongside a fitted hood to optimise thermal efficiency and reduce unnecessary fabric weight.
  • Universal Compatibility: Conveniently fits any sleeping bag and features shoulder-level snap connectors to secure the liner inside Sea To Summit sleeping bags for hassle-free entry and exit.
  • Freshness and Easy Care: Treated with HeiQ Fresh odour control to combat bacterial growth, this quick-drying liner is easy to clean and machine washable to help preserve the lifespan of your sleeping bag.
  • Eco-Friendly Construction: Crafted using recycled fibres and bluesign-approved materials to lower environmental impact without sacrificing high-performance durability.
  • Compact Storage: Packs down ultra-small into its dedicated stuff sack (included) for effortless transportation on multi-day backcountry trips.
When used in combination with an appropriately insulated ground pad and sleeping bag, the Sea To Summit Reactor Lightweight Sleeping Bag Liner can boost your overall sleep system temperature by up to 4 °C (7 °F).
Yes, during warm summer conditions or mild indoor camping, the Sea To Summit Reactor Lightweight Sleeping Bag Liner can serve as a standalone sleep cover when wearing base layers; however, note that the knit fabric is designed for warmth and breathability rather than wind protection.
The Sea To Summit Reactor Lightweight Sleeping Bag Liner features integrated snap connectors at the shoulders that attach directly to compatible Sea To Summit sleeping bags, preventing the liner from twisting or shifting as you move during the night.

Brand : Sea To Summit

SKU: S2ST-053203

Model # : 053203

Barcode : 9327868169764  (AD-2)

Weight : 270g

Dimensions : 206 × 80cm

Packed Size : 18 × 10 × 10cm

Recommended User Height : 198cm

Liner Material : 100% Post-Consumer Recycled Polyester

Stuff Sack Material : 100% Polyester

Free shipping on orders over $140 to Australia*
Shipping on small orders (under $140) only $9.95
Shipping on all orders to NZ only $9.95
Express shipping to Australia & NZ only $15

Standard Shipping (AU) – FREE on orders over $140 and $9.95 on orders under $140. Orders are dispatched within 1 business day. Click here for shipping delivery times

Select ‘Standard Shipping – Auspost Only’ if you would prefer your parcel is sent with Auspost. Otherwise it will be shipped with any of our available carriers. Auspost Only shipping is not available on some very heavy/bulky orders.

Express Shipping (AU/NZ) – Need it faster? Express Shipping is available for $15. Express Shipping is not available on heavy/bulky orders. Orders placed before midday on business days are usually dispatched same day (otherwise within 1 business day). Delivery times in the table below.

Click and Collect – Shop online and collect in our Milton, Brisbane store, free for all orders. Orders are usually ready within 2 hours (during opening hours). Click here for address and opening hours.

Terms and conditions apply, click here for a full overview of our shipping policies

Manufacturing defects covered, replaced or repaired if soon after purchase.

  • If you have selected the wrong product/size for you, or want to exchange/return for any reason except for warranty or our error, this is referred to as a 'change of mind' return.
  • Not all products are eligible for change of mind returns (click here for excluded products).
  • Once you submit a Return Request, we will provide return instructions via email (along with a prepaid return label if applicable). Please wait to receive this before returning any items (Try 2 Anything excluded)
  • Change of mind returns can be resolved by your choice of exchange, full store credit, or a refund. Refunds are subject to a $19.95 admin fee.

For a full overview of our returns and warranty policies, see Returns and Warranties

Help other Wildfire Sports customers shop smarter by writing reviews for products you have purchased.

Write a product review

Others Also Bought

More From This Category