Ultra-light and technical, these Spark Series bags are designed to keep you as warm as possible while minimising packed weight and size.
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/
The ULTRA-DRY 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

• Contoured mummy shape for efficient insulation
• 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
• Ultralight 7D fabrics for minimal weight and packed size
• RDS 850 Loft Premium Goose ULTRA-DRY Down for maximum insulation value
• Vertical box baffles in the torso area accommodates extra down and boosts warmth around the core, vertical baffles on chest optimises positions of down to prevent it moving during use
• Lower part of the bag uses a sewn through horizontal baffle construction to minimise weight
• zip with two sliders aids access and allows ventilation from mid-section of bag
• Draft tube prevents heat loss through the zipper
• Includes hood draft collar
• Materials:
• Shell: 100% Nylon
• Lining: 100% Nylon
• Primary Filling Material: GOOSE DOWN (Min. 90% Down)
• Stuffsack: 100% Nylon excluding Trims

Specifications

• Comfort Temperature Rating: 4°C
• Lower Limit Temperature Rating: -2°C
• Extreme Temperature Rating: -18°C
• Weight: 490 grams
• Fill: 850 Loft Ultra-Dry Down
• Fill Weight:300 grams
• Packed Dimensions: 25 x 13 x 13 cm
  
• Compressed Volume:2.5 Litres
• User Measurements
• Max User Height: 183cm
• Chest Circumference: 150cm
• Hip Circumference: 130cm
• Foot Circumference: 88cm

850 LOFT ULTRA-DRY DOWN

850 Loft
850 Fill Power indicates that 1 oz of down will re-expand to over 850 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.
ULTRA-DRY Down
ULTRA-DRY Down is a permanent nano-level water repellent polymer treatment applied to our down which protects it from external moisture and condensation from inside the bag virtually eliminating the negative effects moisture has on down.

RDS CERTIFIED DOWN

All Sea to Summit sleeping bags use only down which is certified according to the Responsible Down Standard. The RDS is helping shift the entire down and feather industry towards more humane animal rearing and handling practices.
Overseen by the industry leading Textile Exchange, the RDS requires independent, third-party assessments of all aspects of animal rearing and handling throughout the entire supply chain. By using only down that meets the audited requirements of the RDS, we can have confidence that each phase of the collection process has been completed with the welfare and ethical treatment of waterfowl in mind.
To learn more about RDS, visit responsibledown.org

EN RATING

The EN13537 is a European standard for sleeping bags that provides three temperature levels to help guide you when choosing a bag.

Comfort
The temperature at which a standard woman can expect to sleep comfortably in a relaxed position. If you are female or consider yourself a cold sleeper, use this rating to decide the coldest temperature the sleeping bag is suitable for. We emphasise the Comfort temperature for our women’s specific sleeping bags.
Lower Limit
The temperature at which a standard man can sleep for eight hours in a curled position without waking. If you consider yourself a warm sleeper, use this rating to decide the coldest temperature the sleeping bag is suitable for. We emphasise the Lower Limit temperature for all our unisex sleeping bags.
Extreme
This is a survival only rating for a standard woman. Between the lower limit and the extreme rating a strong sensation of cold must be expected and there is a risk of health damage due to hypothermia. This is an extreme survival rating only; we do not recommend you rely on this rating for normal use.