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Spark -18C/0F Down
Extreme cold sleeping bag - Men -
Home delivery from 15/09/2026
60 days to change your mind
No subject to promotional offersThe Spark -18C/0F Down sleeping bag from Sea to Summit is an ideal sleeping bag for adventurers who prioritise comfort when expedition conditions become extreme.
The shape of this model has been designed to fit your body shape as closely as possible, with a resized hood and improved zips. Ultra-lightweight, it offers an exceptional weight-to-warmth ratio, with an 850+ fill power. Compact, this minimalist bag is perfect for long hikes and provides an excellent balance between volume and performance.
The mummy shape helps retain maximum warmth, and it is also filled with 850 CUIN RDS down treated with Ultra-Dry™ to make it moisture resistant, ensuring it maintains its performance in all conditions. Its very lightweight 10D nylon structure offers minimal bulk and good breathability. For your comfort, the Spark features sewn-in baffles around the torso to prevent it from slipping during the night. This model includes a three-quarter length zip and a draft tube integrated into the zipper to prevent heat loss.
- Optimal warmth-to-weight ratio
- Moisture-resistant down
- 2 closure systems
- Adjustable hood with drawcord
- Quilt Lock cover attachment system
- Main zip along 3/4 length with zip guard and 2 sliders
- PFC-free product
Composition:
- Filling: 850 CUIN goose down
- Outer fabric and lining: 10D nylon
| Size | Regular | Large |
| Dimensions (cm) | 185 x 155 | 198 x 165 |
| Compressed volume (L) | 9.9 | 10.6 |
| Weight (g) | 1113 | 1204 |
| Filling weight (g) | 840 | 945 |
| Responsible Down Standard (RDS) | 100% of the down used in our sleeping bags and quilts is independently certified according to the Responsible Down Standard (RDS). The RDS certifies animal welfare requirements and traceability from source to final product. Purchasing RDS-certified products demonstrates a demand for better animal welfare practices in the down and feather supply chain. Sea to Summit is RDS certified. |
| 850+ loft Ultra-Dry Down | 850+ Fill Power indicates that one ounce (30g) of down will re-expand to over 850 cubic inches after compression. Higher loft means less down is needed to achieve the same temperature, which is crucial for high-performance sleeping bags. The loft and quality/composition of the down are independently tested by the International Down and Feather Laboratory (IDFL) – a copy of the certification is provided with every Sea to Summit sleeping bag. The down is responsibly sourced, RDS certified, and treated with our PFC-free Ultra-Dry Down™ treatment. |
| Quilt Lock System | The QuiltLock system uses press studs located at the shoulders and feet of Sea to Summit sleeping bags, as well as the quilt / footbox straps to attach a quilt to the sleeping bag. This adds thermal performance and versatility to your sleep system: your integrated quilt now works for ultralight summer adventures and transforms your three-season bag into a four-season sleep system. |
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