Ultralight Thermal Sleeping Bag Liner – Warmth Without the WeightAdd meaningful warmth and comfort to any sleeping bag with this Ultralight Thermal Sleeping Bag Liner. Featuring a soft velvet inner lining and a down-cotton blend fill (cotton base layer, down top layer), this mummy-style insert traps heat efficiently while remaining packable enough to carry on any adventure.Designed for adults up to 1.8m tall, it fits inside most standard sleeping bags and works as a standalone liner in warmer conditions. Whether you're camping in the US Rockies, hiking in the Swiss Alps, or backpacking across Southeast Asia, this liner extends your sleeping bag's temperature range and adds a layer of hygiene between you and your bag.Key Features Velvet Inner Lining: Soft, skin-friendly fabric for a comfortable night's sleep Down-Cotton Blend Fill: Cotton at the base for structure, down at the top for superior insulation Mummy Shape: Contoured design minimizes cold spots and maximizes heat retention Ultralight & Packable: Compresses into a compact carry bag — i for backpacking and travel Versatile Use: Works as a sleeping bag insert in cold conditions or a standalone liner in summer Fits Adults Up to 1.8m: Accommodates most adult body sizes comfortably Technical Specifications Specification Detail Inner Lining Velvet (soft, skin-friendly) Fill Material Down-cotton blend (cotton base, down top) Shape Mummy style Suitable For Adults up to 1.8m height Use Case Sleeping bag insert / standalone summer liner Packability Ultralight, compresses into carry bag Season Summer primary; cold-weather supplement Who Is This Liner For?This sleeping bag liner is for backpackers, campers, hikers, and frequent travelers who want to boost their sleeping bag's warmth rating, add a hygienic barrier, or travel light with a standalone summer sleep solution. It's an essential addition to any outdoor sleep system.Frequently Asked QuestionsCan I use this liner without a sleeping bag?Yes. In warmer summer conditions, this liner can be used on its own as a lightweight sleep solution in hostels, guesthouses, or mild-weather camping.Does it fit inside a standard mummy sleeping bag?Yes. The mummy shape is designed to fit inside most standard mummy-style sleeping bags for adults up to 1.8m tall.How much warmth does it add?The down-cotton blend fill adds meaningful insulation, making it suitable as a temperature booster in cold conditions or a primary layer in summer.