Description
Ultralight Winter Sleeping Bag
The Criterion Prime 700 is a 5 season down sleeping bag rated to –18°C, built for serious cold-weather camping, alpine mountaineering, and minimalist bivvying. Whether you’re pitching in the Scottish Highlands or sleeping above the snowline, this bag delivers reliable warmth without excess bulk.
Weighing just 1110g, the Prime 700 achieves its performance through 700g of ethically sourced 850 fill power White Polish Goose Down, housed in a Pertex Quantum ripstop shell. The shell’s 35g/m² weight helps reduce pack load while maintaining durability and DWR protection against condensation and damp gear.
In this latest version, the Prime 700 features an updated Pertex Quantum ripstop shell that contributes to a total weight reduction of approximately 100g compared to earlier models. Whilst retaining its DWR treatment, refinements in construction and fabric efficiency allow for improved packability without compromising durability or thermal performance.
Trapezoid baffle construction eliminates cold spots, ensuring consistent insulation across the bag’s full length. The compact pack size—just 17 × 17 × 36 cm—makes it ideal for fast-moving winter expeditions where space and weight matter.
Temperature ratings are independently verified by Leeds University, confirming the Prime 700’s comfort performance at –18°C. This makes it suitable for extended use in harsh UK winters and alpine environments where reliability is non-negotiable.
Technical Features
- 700g of 95:5 Diamond Grade White Polish Goose Down (850 FP)
- Pertex Quantum ripstop shell (35g/m²) with DWR treatment
- Trapezoid baffle construction for thermal consistency
- Full-length YKK two-way zip with anti-snag insulated baffle
- Insulated neck baffle and cowl hood with one-hand drawcord
- Internal pocket and hanging loops
- Supplied with compact stuff sack and mesh storage bag
- Suggested Max user height: 190cm (6’3″)
How the Prime 700 Is Designed for Real-World Use
Built for serious cold-weather conditions, the Prime 700 is engineered to perform in environments where weight, warmth, and reliability are critical. Whether you’re winter trekking in the UK or bivvys in alpine terrain, its –18°C comfort rating and ultralight build make it a trusted companion for demanding expeditions.
The Prime 700 is designed for conditions such:
- 5 Season Sleeping Bag
- Winter camping in UK uplands and exposed terrain
- Alpine mountaineering and bivvys
- Cold-weather wild camping and multi-day treks
In the Field
The Prime 700 has been trusted by serious winter backpackers for years. In Trail Magazine’s 2018 Gear Guide, it was praised for its warmth, length, and suitability for year-round use:
“With a comfort temperature of minus 18°C, you can camp out in Criterion’s 4-season Prime 700 all year round. The mummy cut bag has a full-length zip and insulated neck baffle, plus it has good length… if you’re winter backpacking the 870 fill power down keeps you impressively warm.”
Why Choose the Prime 700?
Unlike heavier expedition bags, the Prime 700 balances warmth and packability for active winter use. It’s ideal for trekkers and mountaineers who need reliable insulation without compromising on weight. The updated shell fabric offers a modest weight saving—useful for gram-counters—but the core value remains in its proven down quality, construction, and field-tested performance.
FAQs
**Is this suitable for Scottish Highlands in January?**
Yes. The –18°C comfort rating covers typical winter lows in UK mountain regions.
**Can I zip this to another Criterion bag?**
Yes. All Criterion sleeping bags feature zip compatibility—even across models.
**Is the down ethically sourced?**
Absolutely. All down is certified under the [DOWNPASS](https://www.criterion-sleepingbags.co.uk/technology/down-policy/) standard.
