Sea to Summit Hamelin Women's Synthetic Sleeping Bag

The Sea to Summit Hamelin Women's Synthetic Sleeping Bag is a women's-specific mummy bag filled with Revive Loft recycled synthetic insulation, rated to an ISO Comfort temperature of 30°F (-1°C) in the 30°F version and 15°F (-9°C) in the 15°F version. Built for light trekking, backpacking in wet conditions, paddle touring, and car camping, the Hamelin insulates reliably even when damp, a meaningful advantage over down in rain-heavy or high-humidity environments. The bag is available in two temperature ratings (30°F and 15°F) and two lengths (Regular, for users up to 170 cm / 5'7"; Long, for users up to 183 cm / 6'0").

Synthetic Insulation That Works When Wet

Revive Loft insulation is constructed from 100% RCS-certified post-consumer recycled polyester with hollow-core fibers that trap insulating air. Unlike down, synthetic insulation retains meaningful loft and warmth even after exposure to moisture. This makes the Hamelin a practical choice on multi-day trips where condensation, rain, or paddle spray is unavoidable. The Hamelin's insulation is strategically layered to concentrate warmth at the core and footbox, the areas where heat loss matters most during sleep.

Ventilation Across a Range of Temperatures

The Hamelin's Free-Flow zipper system gives sleepers meaningful control over temperature without fully unzipping. The right-side full-length YKK #5 zipper runs two sliders that extend through the footbox, so the bag can be opened flat as a quilt or vented at the feet without unzipping the entire bag. The left-side half-length YKK #5 zipper lets both arms out independently, useful when camp chores or changing temperatures call for more freedom of movement without fully opening the bag.

Women's Contour Fit and Thermal Details

The Women's Contour shape is cut narrower at the shoulders and roomier between the hips and knees, following the geometry of a woman's body rather than a unisex average. This fit reduces dead air space that the body must heat, improving thermal efficiency without sacrificing the room needed to roll over or sleep in a side or figure-four position. A technical hood, draught collar, and draught tubes along the zipper seal in warmth at the head and neck, the points where heat escapes fastest in cold conditions.

Materials and Sustainability

Shell, lining, and insulation are all made from 100% post-consumer recycled polyester. The fabrics carry bluesign approval and RCS (Recycled Claim Standard) certification, which verifies recycled content through third-party audit across the supply chain. The Hamelin is part of Sea to Summit's 1% for the Planet commitment, with a portion of revenue directed to biodiversity conservation organizations. A compression sack is included.

Features

• Revive Loft insulation: 100% RCS-certified post-consumer recycled synthetic fill; insulates when wet
• Free-Flow zipper system: right-side full-length YKK #5 two-way zipper with double sliders through the footbox; left-side half-length YKK #5 two-way zipper for arms-free use
• Women's Contour shape: narrower shoulders, roomier hips-to-knees for side and figure-four sleeping
• Thermal retention features: technical hood, draught collar, and draught tubes along the zipper
• ISO-tested temperature ratings: women's bags rated to ISO Comfort standard
• Includes compression sack; bluesign-approved, RCS-certified recycled fabrics throughout

Specifications

Who This Is For and Isn't

The Hamelin Women's Synthetic Sleeping Bag suits women who camp, backpack, or paddle tour in conditions where moisture exposure is likely and synthetic insulation's wet-weather reliability matters more than the packed volume of a comparable down bag. The 30°F version covers three-season use; the 15°F version extends into colder shoulder-season conditions. The Regular length fits users up to 170 cm (5'7"); the Long fits users up to 183 cm (6'0").

The Hamelin cannot be zipped to another Hamelin or to a unisex bag. The zipper configuration does not support coupling. Buyers for whom packed volume is the primary constraint may find a down bag a better fit, as synthetic insulation compresses less than down at equivalent warmth ratings. The 30°F version is not designed for winter or sub-freezing expedition use.

Common Questions

How does Sea to Summit rate the temperature on women's bags?

Sea to Summit tests sleeping bags to the ISO 23537 standard, which produces two ratings: an ISO Comfort rating (the lowest temperature at which a woman should stay warm) and an ISO Lower Limit (the lowest temperature at which a man should stay warm). Women's Hamelin bags are listed using the ISO Comfort rating, so the "30°F" bag is rated to an ISO Comfort of 30°F (-1°C) and an ISO Lower Limit of 18°F (-8°C).

Is the Hamelin a good bag for cold-weather backpacking?

The Hamelin Women's Synthetic Sleeping Bag handles three-season and shoulder-season conditions well. For cold-weather backpacking where packed volume is critical, the synthetic insulation's larger compressed size compared to down is worth considering: the 30°F Long compresses to 13.3 L and the 15°F Long to 21.5 L. Buyers prioritizing the smallest possible pack footprint may want to compare a down bag at the same temperature rating.

Can the Hamelin be machine washed?

The Hamelin Women's Synthetic Sleeping Bag can be washed in a front-loading machine. A top-loading machine with a central agitator is not recommended, as the agitator can stress lightweight gear and insulation during the wash cycle.

Can two Hamelin bags be zipped together?

Hamelin bags are not designed to be zipped together. The zipper configuration, a full-length zipper on one side and a half-length zipper on the other, does not support bag coupling, and no zipper coupling is available for this model.

Can the Hamelin be used as a quilt?

The Hamelin Women's Synthetic Sleeping Bag can be opened fully flat as a quilt. The right-side full-length zipper uses two sliders that run through the footbox, allowing the bag to be unzipped completely along its length and used as a blanket or quilt when temperatures are mild.