Guide to Choosing the Right Sleeping Bag

Outdoor activities, Trekking, How to choose -guides by Varuste.net, 25.3.2026

In collaboration with Rab

A good night's sleep is the foundation of any successful adventure. Whether you're scaling high peaks or enjoying a weekend camping trip in the local woods, choosing the right sleeping bag is crucial. Rab has been crafting sleeping bags for over 40 years, and in this guide, we’ll walk you through the most important things to know before making your purchase.

1. Insulation: Down vs. Synthetic

The first question is always about the insulation. Both have their strengths:

Down: Offers the best warmth-to-weight ratio and packs down incredibly small. Rab uses ethically sourced and often Nikwax hydrophobic down, which repels moisture better than traditional down. Choose down when weight and packability are your top priorities.
Synthetic Insulation: Bags like Rab’s Solar Eco series are durable and retain their insulating properties even when damp. They are an excellent choice for humid conditions, paddling trips, or the budget-conscious camper.

2. Temperature Ratings – What do they actually mean?

Sleeping bags typically use ISO-standardized test values:

Comfort: The temperature at which you can sleep comfortably and relaxed all night.
Limit: The temperature at which you can sleep for eight hours without waking up from the cold (often in a fetal position). Rab often uses this number in product names (e.g., Ascent 600 -7°C).
Extreme: For emergency use only – the temperature at which you can survive for six hours without hypothermia. This should not be used as a basis for selection.

Pro tip: If you tend to feel the cold easily, choose a bag based on the Comfort rating.

3. Choose a bag based on your activity

Rab has categorized its collection for different uses to help you find the perfect balance between weight and durability:

Mythic Series: Ultralight performance for climbers and gram-counters. Features the world’s finest 900FP down and innovative TILT technology that reflects body heat back to you.

Neutrino Series: An alpinist classic. Lightweight, slim-fit design, and very high-quality down. Perfect for treks where every gram counts.

Ascent Series: A versatile and durable "workhorse." A slightly wider cut offers more comfort and room to move. An excellent choice for your first sleeping bag.

Andes & Expedition: Designed for extreme conditions, high mountains, and Arctic expeditions.

4. Details Matter

Shape: The mummy shape is the warmest because it has the least empty space to heat up. Rab’s women’s models account for different body shapes and warmth requirements. Draft Collar and Zip Baffle: Ensure the bag has a plush collar to prevent warm air from escaping through the zipper or head opening. Sleeping Mat: Remember, no sleeping bag works without sufficient insulation from the cold ground. Check your sleeping mat’s R-value!

Rab Sleeping Bags

Or browse below:

Sports‪»Trekking‪»Sleeping bags etc.‪»Sleeping bags‪»3-season sleeping bags‪»

Essential cookies
Optional cookies

Guide to Choosing the Right Sleeping Bag

1. Insulation: Down vs. Synthetic

2. Temperature Ratings – What do they actually mean?

3. Choose a bag based on your activity

4. Details Matter

Or browse below:

You might also be interested in

Comparison: Garmin Fenix 8, Tactix 8, and Enduro 3

Don't let thirst catch you by surprise - CamelBak is every mover's most important piece of gear

How to Choose the Right Socks for Outdoor Activities