Mountain Equipment Snowline Sleeping Bag (-23°C/-9°F)

This is the lightest sleeping bag in the expedition-class category. Exceptionally light when used on its own, it still provides ample room to accommodate down clothing when conditions demand maximum performance.

As part of the Extreme Expedition sleeping bag series, the Snowline is engineered as a lightweight yet highly capable option for mountaineering, remote ski missions, and serious cold-weather endeavours.

The Snowline is filled with 831g of top-tier European goose down, boasting a minimum 800-fill power and full CODEX certification. This insulation is paired with a lightweight yet rugged GORE-TEX WINDSTOPPER® 10 denier outer fabric, resulting in a sleeping bag that balances serious warmth with excellent breathability and resistance to the elements.

Bags in the Extreme Expedition range, including the Snowline, employ the most advanced baffle design available. V-shaped baffles across the chest and thighs maximise down coverage and eliminate cold spots. Trapezoid baffles in the centre section prevent down from shifting during use, while full-length side baffles help retain the bag’s thermally efficient box-like shape. The hood features a complex seven-baffle system that keeps down evenly distributed around the head for sustained warmth and protection. Meanwhile, the anatomically sculpted foot box is insulated using a six-baffle design that targets warmth where it's needed most.

The density and placement of down are carefully varied throughout the bag. Heavier fills on the underside resist compression from body weight, while lighter fills above allow for maximum loft. Internally, the trusted EXL® elasticated stitching system draws the liner fabric inwards, minimising dead air spaces, reducing draughts, and allowing the down to loft more efficiently for superior warmth.

A full-length Gemini™ zip baffle significantly reduces heat loss along the zip, which is often a vulnerable area in cold conditions. The Lode Lock™ magnetic closure is low-profile and intuitive to operate in the dark, working seamlessly with the collar drawcords. Inside the bag, there is a mesh pocket and a secure zipped pocket to keep essential items easily accessible.

The generous Expedition fit has been tailored for both comfort and practicality. It allows space for wearing additional down layers on colder nights. The roomy foot box, lined with breathable GORE-TEX WINDSTOPPER® fabric, also accommodates wet gear or boot liners without sacrificing comfort.

With a Good Night’s Sleep Temperature rating of -23°C (-9°F), the Snowline stands as a warm, dependable, and durable sleeping bag built to meet the challenges of high-altitude and extreme mountain conditions.

Features

• GORE-TEX INFINIUM™ 10D outer shell is durably light, highly breathable and rain-resistant
• 831g of 90-10 Russian Goose Down with a minimum fill power of 800
• Expedition fit with EXL® system is both roomier and has improved loft and thermal efficiency
• V chest and foot baffles & Trapezoid main body baffles
• Ground level side seams with V-side baffle
• 7 baffle low volume anatomically shaped hood
• 6 baffle anatomically shaped offset foot-box
• Full length Gemini™ zip baffle and integrated neck collar with Lode Lock™ closure
• GORE® THERMIUM™ 10D inner foot-box and hood lining
• Inner pocket for keeping essentials warm and dry
• Supplied with waterproof roll-top stuff-sack and storage cube
  
  

Specifications

Technology

	Down 800 Their very best Eastern European goose down. Sourced from Western Russia, with a minimum down cluster content of 90% and individually tested to ensure a minimum fill power of 800 cubic inches. DOWN CODEX approved.
	GORE-TEX INFINIUM™ GORE-TEX INFINIUM™ fabrics combine multilayer membrane technology with high performance fabrics to produce materials that are windproof, highly breathable and extremely resistant to rain and snow. Weather resistance, protection and comfort are the INFINIUM™ hallmarks.
	Down Codex® The DOWN CODEX® is our multi-award-winning certification scheme that considers the environmental, ethical and animal welfare matters relating to our down supply chains. It is grounded in comprehensive and transparent auditing that ensures traceability and quality.
	Fair Wear As a member of Fair Wear, Mountain Equipment is committed to implementing the highest standards of working conditions. Mountain Equipment were awarded 'Leader Status' by Fair Wear Foundation in 2016 and has been awarded their highest accolade for performance every year since.

Detail Shots

	Vertically aligned V-baffles on the chest and foot piece, 14:7cm Trapezoid baffles throughout all other parts of the bag results in minimal down migration and maximum possible warmth in all situations.
	Our Lode Lock collar closure with its auto-locating closure combines all the advantages of a magnetic fastener with those of a mechanical lock. Its one-handed quick release closure uses magnets to draw the locking mechanism together and ensure that once connected it cannot be accidentally opened.
	7 baffles provide exceptional down control for performance and excellent insulation. The DC7 LV hood reduces weight, has less deformation when cinched down small, and offers single handed closure and easy-run dual tether draw cords for greater ease of use in extreme conditions.
	A six-baffle foot piece, Mountain Equipment's most advanced design, and featuring both their Bulls Eye Technology and offset Sharks Toe foot construction. Its highly sophisticated baffle system maximises thermal efficiency for the coldest and most demanding environments, ensuring warm feet night after night.
	GORE-TEX INFINUM™ 10D outer shell is durably light, highly breathable and rain-resistant.
	Inner pocket for keeping essentials warm and dry.

More Information

Extreme Expedition Sleeping Bags

Engineered to withstand extreme cold in the most hostile environments on earth. With durably rain-resistant fabrics and construction optimised to maximise and maintain warmth for extended periods these bags are built specifically for the needs of explorers and mountaineers undertaking the most committing journeys in the highest, coldest and most remote locations.

Shop the Expedition Range

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