Versatile, roomy, and reliably warm.Sea to Summit says:A backpack-capable sleeping bag with a higher level of comfort than traditional mummy bags. For a few extra grams and larger packed size, Hamelin brings the benefits of synthetic insulation in wet/sandy environments. Designed for comfort andperformance, the relaxed mummy fit offers plenty of room to move. The full-length side zipper extends throughout the foot box, along with a half-length zipper on the opposite side it provides ventilation and versatility.Our VerdictThe Sea to Summit Hamelin -9C blends reliable performance with a relaxed fit that feels less restrictive than most mummy-style designs. The contoured, women’s-specific fit allows for more natural movement without creating excess dead space, and the anatomically shaped footbox helps maintain warmth where its needed most.The bag is rated to a lower limit of -9C, and it performs well for most winter trips. The double-zip system, full-length on one side, half-length on the other, allows for excellent venting options or even converting the bag into a quilt on warmer nights.At 1953g (Regular), its on the heavier side. Still, the durable 50D shell, smooth-running zip with plough, and thoughtful extras like the draft collar and pillow-compatible hood make it feel like a fully considered system rather than a pared-back option.If youre looking for comfort and resilience across a range of conditions, and dont mind a bit of extra bulk, the Hamelin is a strong all-rounder.- Reviewed by Ultralight Outdoor GearFeaturesBluesign approved, 20D recycled polyester shell with PFC-free WR. 20D bluesign-approved recycled polyester liner.100% RCS-certified, postconsumer, recycled, multidenier synthetic insulation.Free Flow zipper system and relaxed mummy fit for comfort and performance across multiple seasons, varying weather and challenging environments.SpecificationsRegularWeight: 1953gComfort: -3C | 27FLower Limit:-9C | 15FMax User Height: 170cmFill weight: 1210gFit: Contour Womens-specific relaxed mummyLongWeight: 2261gComfort: -3C | 27FLower Limit:-9C | 15FMax User Height: 185cmFill weight: 1375gFit: Contour Womens-specific relaxed mummyMaterial & ConstructionFabric – Bluesign approved, 50D recycled polyester shell, PFC-free DWR. 50D bluesign- approved recycled polyester liner.Insulation – 100% RCS certified, postconsumer recycled, multidenier polyester. Offset insulation avoids cold spotsZip – #5 Side zipper continues through footbox. Zipper plough, double sliders. #5 half length zipper on opposite side.Neck Draft Coller – Front draft collarFoot Box – Generous, anatomically shaped footbox avoids cold spotsDraft Tube – YesPillow Integration – Hood accommodates Regular Aeros PillowHelp & advice:Womens Sleeping Bags How do they differ?The Ultimate Guide to Lightweight Sleeping BagsTime-Saver Guide to Choosing a Sleeping BagSea to Summit Sleeping Bag & Quilt GuideSea to Summit Sleeping Mat GuideAbout Sea to Summit

Versatile, roomy, and reliably warm.Sea to Summit says:A backpack-capable sleeping bag with a higher level of comfort than traditional mummy bags. For a few extra grams and larger packed size, Hamelin brings the