Sea to Summit Reactor Sleeping Bag Liner – Regular Compact (78 x 31.5)

Upgrade your sleep system with the Sea to Summit Reactor Sleeping Bag Liner in Regular Compact (78 x 31.5). This insulated liner adds warmth and personal hygiene to any bag, making it a practical layer for cool nights, hostel stays, or-duty trips where space and weight matter. The soft, knitted fabric offers generous stretch, moving with you for a comfortable night’s rest, while the liner works across various bag shapes for versatile use.

Warmth and comfort you can feel

Thermolite Pro technology uses knitted hollow-core fibers and infrared ceramic pigments to reflect your body heat back toward you. The result is a discreet warmth boost inside your sleeping bag—without adding bulk—so you can stay cozy in unpredictable environments.

Fit, flexibility, and convenient design

Designed in a mummy shape with a drawcord footbox, the liner can be opened or closed to tailor comfort. It also integrates smoothly with the Free-Flow Zip system found in select Sea to Summit bags, helping you maintain a cohesive sleep setup.

• Knitted fabric provides stretch and freedom of movement
• Drawcord footbox for adjustable warmth and comfort
• Seamless compatibility with Free-Flow Zip systems

Odor control and reassurance on extended trips

HeiQ Fresh odor control technology helps keep the liner feeling fresh after longer use, supporting a more hygienic sleep routine when you’re away from home.

• HeiQ Fresh helps maintain freshness between uses
• Lightweight, breathable knit for easy layering and quick drying

Durability and a trusted promise

Sea to Summit offers a lifetime guarantee on this liner, underscoring the brand’s commitment to reliable gear that endures through years of adventures. The Reactor liner is designed to work with a variety of sleeping bag shapes, preserving comfort and hygiene across environments.

In practical terms, this liner can add warmth on chilly nights, enhance personal comfort during multi-night trips, and simplify packing by reducing the need for multiple sleeping bag covers. For travelers who value flexibility, hygiene, and a lightweight boost of warmth, the Reactor liner represents a thoughtful addition to a compact sleep system.