Mountain Equipment Helium GT 250 Sleeping Bag (1°C/34°F)

Light enough to carry on even the most minimalist of warm-weather adventures, this sleeping bag still provides a little extra space for added comfort.

Offering a roomier fit compared to the standard Helium collection, the Helium GT series has been developed with extended use in mind, providing exceptional comfort for those who prefer a bit more space to move. Filled with 289g of responsibly sourced, minimum 700-fill power duck down certified under the DOWN CODEX programme, and wrapped in a high-performance, 100% recycled Helium 20D outer fabric, the Helium 250 is an impressively efficient sleeping bag that remains lightweight and easily packable—ideal for minimalist warm-weather travel.

Slant-baffle construction runs through the main body of the bag, enhancing warmth, improving compressibility, and preventing the down from shifting—ensuring consistent insulation and eliminating cold spots. A four-baffle system concentrates warmth around the feet, while a five-baffle configuration in the hood enhances comfort and maintains precise down placement for reliable warmth.

Inside, the bag features a 100% recycled Supersoft 20D lining treated with PFAS-free DWR, offering both breathability and durability for lasting comfort. A full-length Gemini™ zip baffle helps to prevent heat loss along the entry point and includes a stiffened structure to avoid snags. Practical in low light, the Lode Lock™ magnetic closure and collar drawcords are simple to operate in the dark.

The Helium GT uses a more generous GT Fit, retaining the tapered Alpine profile while providing greater internal volume without compromising thermal performance. With a Good Night’s Sleep Temperature rating of 1°C (34°F), the Helium GT 250 is perfectly suited for long warm-weather backpacking trips and extended camping journeys.

Features

• The outer shell is made from 100% recycled HELIUM 20D fabric, which is exceptionally light and highly breathable with a PFAS-free DWR treatment.
• It is filled with 289g of 90-10 pure duck down, offering a minimum fill power of 700.
• The GT fit provides ample space for comfort and accommodates a variety of sleeping positions.
• The body features slanted box-wall baffles combined with stitch-through baffle construction.
• Mid-level side seams contribute to the overall performance and structure.
• The anatomically shaped hood uses five baffles to maximise comfort and thermal efficiency.
• A four-baffle, anatomically shaped and offset foot-box ensures focused warmth where it’s needed most.
• The full-length Gemini zip baffle includes a 140cm zip and an integrated neck collar secured with a Lode Lock closure.
• The interior uses a 100% recycled Supersoft 20D lining with PFAS-free DWR for comfort and breathability.
• It is supplied with a waterproof roll-top stuff sack and a storage cube for convenience and protection.
  

Specifications

Technology

	Down 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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