The Spark™ Series spans everything from an ultralight liner to an expedition weight mid-winter bag. While the end usage is very different, they reflect a design ethos of matching weather conditions to the lightest bag possible. The secret to the impressive performance is a combination of premium materials and careful design. The RDS 850+ Loft premium goose down, light-gauge #3 YKK zip and high performance 10D Nylon shell and 7D lining fabrics, set the stage for superior performance. These materials are combined with a contoured mummy design for efficient insulation, and that mummy design is then tweaked for each model to best fit the use scenario.

Sea To Summit's ULTRA-DRY Down™ water-repellent treatment protects the down from external moisture and condensation from the inside of the bag, virtually eliminating the negative effects moisture has on down. All Sea to Summit Down Sleeping Bags use Responsible Down Standard (RDS) certified down. The ULTRADRY Down™ protection also makes the Spark™ an impressive hard-alpine or adventure racing bag, where every gram is counted and down has never been a viable option.

FEATURES

Ultralight 7D and 10D fabrics for minimal weight and packed size
RDS 850+ Loft Premium Goose ULTRA-DRY Down™ for maximum insulation value
Contoured mummy shape for comfort and efficient insulation
Vertical chest baffles prevent down migration and cold spots
Sewn through construction minimises weight
Sewn through vertical baffles on chest optimises position of down to prevent it moving during use
½ zip with single slider aids access while keeping weight to a minimum
Updated sizing provides extra room for both shoulders and hips while still maintaining insulation efficiency
Includes lightweight Ultra-Sil™ Nano compression bag for compact storage

Combining top quality 850+FP down with an efficient mummy bag design, the Sea to Summit Spark SpIII ultralight sleeping bag is perfect for three season use. Insanely packable and weighing only 655g, this UL sleeping bag is perfect for hiking or bikepacking trips when you don't want to compromise on warmth or weight. The Sea To Summit Spark SpIII Sleeping Bag is ultra-light and technical, the Spark™ Series bags are designed to keep you as warm as possible while minimising packed weight and size.
The Spark™ Series spans everything from an ultralight liner to an expedition weight mid-winter bag. While the end usage is very different, they reflect a design ethos of matching weather conditions to the lightest bag possible. The secret to the impressive performance is a combination of premium materials and careful design. The RDS 850+ Loft premium goose down, light-gauge #3 YKK zip and high performance 10D Nylon shell and 7D lining fabrics, set the stage for superior performance. These materials are combined with a contoured mummy design for efficient insulation, and that mummy design is then tweaked for each model to best fit the use scenario.

Sea To Summit's ULTRA-DRY Down™ water-repellent treatment protects the down from external moisture and condensation from the inside of the bag, virtually eliminating the negative effects moisture has on down. All Sea to Summit Down Sleeping Bags use Responsible Down Standard (RDS) certified down. The ULTRADRY Down™ protection also makes the Spark™ an impressive hard-alpine or adventure racing bag, where every gram is counted and down has never been a viable option.

Features

• Ultralight 7D and 10D fabrics for minimal weight and packed size
• RDS 850+ Loft Premium Goose ULTRA-DRY Down™ for maximum insulation value
• Contoured mummy shape for comfort and efficient insulation
• Uses a full box baffle construction to accommodate extra down and reduce cold spots
• Vertical baffles on chest optimises positions of down to prevent it moving during use
• Full side zip with two sliders provides easy access and extra ventilation options
• Zipper draft tube, hood and front neck draft collar to prevent warmth being lost when it’s needed