Price: $87.87
(as of Nov 22, 2025 08:35:52 UTC – Details)

Sea to Summit Reactor Sleeping Bag Liner

Overview

The Sea to Summit Reactor series insulated sleeping bag liners are designed to extend the comfort range and improve personal hygiene of any sleeping bag. These liners use Thermolite hollow core fibers, which efficiently trap heat and provide a luxuriously soft, comfortable feel.

Features

• Thermolite Technology: The liners utilize Thermolite Pro technology, featuring knitted, hollow-core fibers and absorbing infrared ceramic pigments to reflect the body’s heat back to the wearer for enhanced warmth and comfort.
• Drawcord Footbox: The drawcord footbox can be opened or closed for optimal comfort and integrates perfectly with the footbox of Sea to Summit’s Free-Flow Zip system in select sleeping bags.
• HeiQ Fresh Odor Control: The liners incorporate HeiQ Fresh odor control technology to keep them fresh even after extended use.
• Knitted Fabric: The knitted fabric provides incredible stretch and freedom of movement in this mummy-shaped liner, working seamlessly with sleeping bags of any shape.
• Variety of Models: Available in three different weights (Regular, Extreme, Fleece), these liners can add up to 14F, 25F, or 32F of warmth to the sleep system, respectively.

Pros

• Enhanced Warmth: The liners add significant warmth to any sleeping bag, making them ideal for colder conditions.
• Improved Hygiene: They provide a hygienic layer, extending the life of the sleeping bag by preventing direct contact with the user’s skin.
• Comfort and Flexibility: The stretch-knit fabric ensures optimal comfort and allows for a full range of motion.
• Versatility: Compatible with any sleeping bag, regardless of shape or brand.
• Lifetime Guarantee: Backed by Sea to Summit’s lifetime guarantee for durability and performance.

Cons

• Additional Weight: Although lightweight, the liners do add weight to the overall sleeping system.
• Cost: The purchase of a liner is an additional expense on top of a sleeping bag.
• Care Requirements: While the HeiQ Fresh technology helps with odor control, the liners still require regular washing and maintenance to ensure longevity and performance.

Specifications

• Dimensions: Vary by model, with options such as 85 x 31 inches, 72 x 25 x 4 inches, etc.
• Weight: Ranges from 10 oz (284 g) for the lighter models to 4.72 pounds for the heavier ones.
• R-value or Temperature Grade: Adds up to 25F of warmth for the Extreme model, with varying degrees of warmth for other models.
• Non-PFAS: All models are PFAS-free, ensuring a safer and more environmentally friendly product.

Conclusion

The Sea to Summit Reactor Sleeping Bag Liner is a versatile and effective accessory for enhancing the warmth and hygiene of any sleeping bag. With its advanced Thermolite technology, comfortable stretch-knit fabric, and variety of models to choose from, it’s an excellent addition to any camping or backpacking gear. Whether you’re looking to extend the season of your current sleeping bag or simply want to sleep more comfortably, the Reactor series has a liner that can meet your needs.