Amplitude Down Sleeping Bag (-4°C & -15°C)
Highlights
BEST USE: Car Camping
PERFORMANCE: 2.5 Season
WEIGHT: 2lb 6.6oz | 1095g
COMPRESSED VOLUME: 6.3 liters
Shipping & Returns
We use climate-neutral shipping with DHL GoGreen.
For orders within Germany we charge a shipping fee of 6,95 €.
For international orders, shipping costs 9,95 €.
All orders are usually shipped within 24 hours on working days. Delivery time can take up to three working days Germany-wide and up to six working days internationally, and depends on the shipping service provider.
All orders can be returned within 14 days of purchase. However, for the sake of the environment, please make sure to keep returns as low as possible.
Find Locally
The EN Rating scale is a scientific test to determine the warmth of a sleeping bag. The test produces a Lower rating (for male sleepers) and a Comfort rating (for female sleepers). Both are listed in the features table on the product page.
A unisex sleeping bag with a Lower limit of -10°C means a man should be comfortable down to air temperatures of -10°C. The same bag will also have a Comfort limit, in the realm of -3°C, so a woman would be comfortable down to an air temperature of -3°C. These ratings require a sleeping mat with an R-Value appropriate for expected ground temperatures – without this, the sleeping bag itself is unlikely to keep the sleeper warm enough.
A variety of factors impact sleeping bag warmth - the above temperatures are merely guidelines, not guarantees. It’s important to think of a sleeping bag, an appropriately insulating sleeping pad and a liner as a sleep system. For example - if you plan on sleeping in nighttime air temperatures of -3°C, choose a bag with a gender-appropriate rating of -5°C, plus a sleeping mat with an R-Value of 2.5 to 3, and consider a Reactor thermal liner.


Description
Ideal for adventures with a base camp, the Amplitude down sleeping bag brings spacious luxury and incredibly versatile ventilation options to wherever your travels may take you. Each side of the Amplitude has a full-length side zipper; a third zipper can be found in the foot box.
High-lofting down and quality construction keeps you cosy when it's cold, and the zippers provide temperature regulation up to the point where you remove the upper section and sleep under it as a quilt.
The only thing which might be cosier would be a double version - and we have that, too.
Tech specs
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Best UseCar Camping
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Comes WithUltra-Sil Compression Sack
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InsulationUltra-Dry Down 750+ Loft
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Shell Fabric30D Nylon shell
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Zip OptionsFull length left side, right side and foot box zipper. This provides more options than we have room to list.
Regular -4°C | Regular -15°C | Long -4°C | Long -15°C |
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TECHNICAL FEATURES

The second highest-lofting down used in any of Sea to Summit’s sleeping bags. 750+ Fill Power indicates that one ounce (30g) of down will re-expand to over 750 cubic inches after compression. Higher loft means that less down can be used to achieve the same temperature rating – important for performance sleeping bags. The loft and down quality/composition are independently tested by the International Down and Feather Laboratory (IDFL) – a copy of the certification is supplied with every Sea to Summit sleeping bag. The down is responsibly sourced and RDS certified and treated with the environmentally-friendly Ultra-Dry Down treatment.

100% of the down used in our sleeping bags and quilts is independently certified to the Responsible Down Standard (RDS). The RDS certifies down against animal welfare requirements and tracks it from the source to the final product. The purchase of RDS certified products demonstrates demand for better animal welfare practices in the down and feather supply chain. Sea to Summit is certified to the RDS. To learn more about RDS visit https://textileexchange.org/standards/responsible-down/

Ultra-Dry Down is a non-PFC treatment hydrophobic treatment applied to the down during down processing. It is not a coating (which would reduce the ability of the down to loft), it comprises of very small particles of a polymer that cause the down clusters / feathers to repel water. Ultra-Dry Down is PFC and PFAS-free. Hydrophobic down is not waterproof; but it absorbs less water than untreated down and dries much more quickly.
Ultra-Dry Down does not affect the loft or lifespan of the down, or its breathability. The treatment will last through at least 20 washings.

Down and synthetic bags identified with our zip coupling symbol use a 65 inch #5 YKK full-length zip which allows a unisex left-handed and women's specific right-handed bag to pair together. Designed to pair side by side, each person sleeps in their own bag enabling each of you to take advantage of your bag's unique insulation zones, hood and footbox features - perfect for cozy adventures for two. Bags with full-length #5 YKK zips on both sides can also be coupled together with other pairing bags.
Frequently Asked questions
Warm enough for cool weather camping or travel?
Yes. The quality down and technical construction keeps you warm even on chilly nights. We recommend the Amplitude 5°F paired with a greater than 3.5 R-Value sleeping mat, like the Comfort Plus Insulated. This pairing will keep you warm through shoulder seasons.
Suitable for summer temperatures?
Yes. The full-length side zippers and foot box zipper can be opened for ventilation or remove the upper section completely for use as a comforter.
Fitted with a sleeve to slide in a sleeping mat?
No - instead the lower part of the Amplitude is fully insulated to avoid cold spots – elasticated straps on the underside attach to a sleeping pad of your choice to form a roomy, cozy sleep system.
You have more questions?
Check out our FAQ page HERE and discover even more answers about our products.