Sea To Summit Reactor Midweight Sleeping Bag Liner - Beluga

The Sea to Summit Reactor Midweight Fleece Liner is the versatile, go-to thermal boost for every adventure. Built from stretch-knit fleece with integrated armholes, it delivers exceptional freedom of movement whether you’re a side sleeper or a restless tosser-and-turner. It fits inside any sleeping bag and snaps into Sea to Summit bags for easier entry and exit.
Powered by Thermolite® Pro with Far Infrared (FIR) technology and hollow-core fibres, the Reactor Midweight efficiently traps and reflects body heat to increase warmth without unnecessary bulk—adding up to 6°C | 11°F when used as part of a sleep system.
Unlike a full sleeping bag, the liner is easy to clean and quick-drying. The HeiQ Fresh odour-control treatment helps it stay fresh during extended trips, while reducing how often you need to wash your sleeping bag—helping maintain loft and extend its usable life.

Features:

• Freedom to Move: Stretch-knit construction and armholes allow unrestricted movement in any sleep position.
  
• Thermal Boost: Thermolite® Pro with FIR and hollow-core fibres traps and reflects heat—adds up to 6 °C | 11 °F to your system.
  
• Easy to Clean: Quick-drying fabric with HeiQ Fresh odour control for extended freshness on multi-day trips.
  
• Bag Compatibility: Fits any sleeping bag and snaps into Sea to Summit bags for easier entry/exit.
  
• Extend Bag Lifespan: Reduces need for frequent washing, maintaining insulation loft over time.
  
• Adventure-Ready: Ideal for backpacking, hut trips, bikepacking, and travel where warmth and hygiene matter.

Short
Weight: 330g
Fits Up To Height: 170cm

Regular
Weight: 350g
Fits Up To Height: 185cm

Long
Weight: 355g
Fits Up To Height: 198cm

Please Note: We are unable to accept returns of sleeping bag liners for obvious hygiene reasons unless faulty.
All details are in the listing, so please do NOT buy these if you are unsure of suitability.

At FreshAirJunkie we understand that when you order a product you want it to arrive as soon as possible and with the minimum of fuss, so when an order is received by us, we promise to try our best to dispatch it within 24 hours (Monday to Friday). 

Orders received on a Saturday or Sunday will be packed on the day and dispatched on the following Monday. 

To cut costs for our customers, we dispatch all items via a Royal Mail 48 hour Tracked Service. For larger items or high value items, we mainly use Parcelforce. The estimated delivery time for 2nd Class is delivery by the 3rd working day after posting. Whilst Royal Mail state that most items will be delivered within these time frames it can occasionally take up to 15 days after the due delivery date. 

Unfortunately once the items are with Royal Mail we lose any influence and control over their delivery. 

We ask all customers to be patient when waiting for their products to arrive. If for some reason you have not received your product within a reasonable length of time then please don't hesitate to contact us at: freshairjunkie@hotmail.co.uk so we can look into it for you.

For any items where tracking shows delivered, but the customer denies receipt, the customer agrees to fill in a Royal Mail 'Denial of Receipt' form, so the delivery can be investigated.

Please note, if your parcel arrives opened, or damaged, please check the contents before accepting delivery. Any problems should be noted with the delivery person, or parcels should be refused, Once you accept delivery, we are unable to make a claim to Royal Mail for loss.

It is very important that you provide a delivery address that is accessible and where someone will be in to receive the item, or there is a safe place agreed with Royal Mail for your deliveries.

We do not deliver to Parcel Lockers.

All items will be delivered to the address, and not guaranteed to be handed over in person.

UK Standard Mainland Shipping (excluding Channel Islands, Isle of Man, Northern Ireland, Scottish Highlands/Islands and BFPO)

Free Royal Mail 48 hour service - All Orders up to 3kg

Over 3kg, but under 7Kg is £5.99, and above 7 Kg is £12.99

Expedited Services (Next Day shipping if ordered with cleared funds before 2pm):

*** (Based on Weight, and ONLY applies to UK mainland, and excludes Channel Islands, Isle of Man, Northern Ireland, Scottish Highlands/Islands and BFPO) ***

Up to 1kg £3.99

1.1kg - 2kg £5.99

2.1kg + £15.99

 (Only applies to Week days. This does not include Saturday delivery!)

Channel Islands, Isle of Man, Northern Ireland, Scottish Highlands/Islands and BFPO

Free Royal Mail 48 hour Service - All orders under 2kg

Orders over 2kg, please check before ordering

Please note, all expedited orders will be sent using the selected carrier method. Unfortunately, Royal Mail and Parcelforce cannot guarantee delivery times, especially next day. They still however charge us for the additional service, and we still process the same day and dispatch the same day. We can therefore not refund any expedited order costs, if delivery times are missed.

Multiple item orders and/or high value orders will be sent via an expedited service. This is shown at checkout.

We also reserve the right to choose the most appropriate shipping service as we see fit, which may result in a higher charge to cover for example, added insurance cover.

All shipping costs are as stated at checkout, and there will be no hidden extra charges.