Mountain Equipment Helium GT 600 Sleeping Bag (-10°C/14°F)

Lightweight and highly packable, this sleeping bag offers a slightly roomier fit, making it an excellent choice for lengthy trekking and backpacking adventures during the spring and autumn seasons.

Featuring a more spacious design compared to the standard Helium series, the Helium GT range is crafted for extended use and delivers outstanding comfort for individuals who appreciate a bit more space to move around. Incorporating 656g of duck down with a minimum fill power of 700, approved under the DOWN CODEX standard, along with a premium 100% recycled Helium 20D outer shell, the Helium GT 600 combines exceptional warmth, low weight, and remarkable compressibility—perfect for multi-day expeditions in the cooler months of spring and autumn.

The bag’s body is constructed with slanted box-wall baffles to maximise thermal efficiency, improve compressibility, and prevent the down from shifting—ensuring consistent warmth night after night. A dedicated four-baffle structure at the foot ensures crucial insulation around the feet, while a five-baffle system in the hood delivers tailored comfort and keeps the down precisely in place.

Inside, the bag is lined with a 100% recycled Supersoft 20D fabric that is breathable, durable, and treated with a PFAS-free DWR for added weather resistance. The full-length Gemini™ zip baffle significantly reduces heat loss along the zip line and includes a stiffened backing to prevent snagging. The low-profile magnetic Lode Lock™ closure and easily adjustable collar drawcords are user-friendly, even in the dark.

Shaped with the generous GT Fit, the Helium GT maintains the efficient tapered profile of the Alpine fit while offering greater space without compromising performance. With a Good Night’s Sleep Temperature rated at -10°C (14°F), the Helium GT 600 ensures dependable warmth in colder climates or at elevated altitudes in early spring or autumn.

Features

• The outer shell is made from 100% recycled HELIUM 20D fabric, which is exceptionally light, breathable, and treated with PFAS-free durable water repellent.
• It is filled with 656g of 90-10 Pure Duck Down, offering a minimum fill power of 700 for high loft and warmth.
• The GT fit provides a roomy and comfortable interior, accommodating a range of sleeping positions.
• Slanted box-wall baffles are used throughout the body to maintain even insulation and minimise cold spots.
• Mid-level side seams enhance thermal efficiency and structural balance.
• The anatomically designed hood features five baffles to ensure a snug and thermally efficient fit.
  
• The foot-box is shaped with four offset baffles, concentrating warmth precisely where it’s needed most.
• A full-length Gemini zip baffle runs alongside a 140cm zip and includes an integrated neck collar with a magnetic Lode Lock closure.
• The inner lining is made from 100% recycled Supersoft 20D fabric, treated with PFAS-free DWR for comfort and longevity.
• Each bag comes with a waterproof roll-top stuff sack for packability and a storage cube for long-term care.
  

Specifications

Technology

	Down CODEX® Since 2009, our DOWN CODEX® programme has set high ethical standards for down sourcing, eliminating live-plucking and force-feeding, and ensuring only top-quality virgin down is used, certified to the Responsible Down Standard (RDS).
	Down 700 Down is the finest insulator. Manmade insulations cannot match its warmth-to-weight ratio, compressibility, long lifespan, and softness. Duck Down is great for insulated clothing and equipment for all but the most serious expeditions.
	Helium Helium fabrics are exceptionally light, compressible, and soft. Their densely woven construction ensures the highest levels of down-proofing and wind resistance.

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