SEA TO SUMMIT Spark SPIV Sleeping Bag

Ultra-light and technical, our 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. - Our 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: - 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 - ½ zip with two sliders aids access and allows ventilation from mid-section of bag - Updated sizing provides extra room for both shoulders and hips while still maintaining insulation efficiency - Draft tube prevents heat loss through the zipper - Includes hood draft collar Specifications: - Insulation Type: Down - Down: RDS 90/10 Premium Goose Down - Fabric: 10D Nylon Shell - Fill Power: ULTRA-DRY Down® 850+ Loft - Fill Weight: Regular: 300g, Long: 345g - Shape: Contoured Mummy - Temp Rating: EN 4°c Comfort to -2°c Lower - Weight: Regular: 490g, Long: 560g Technology: Loft: - Loft is the volume for a given weight of down. It is used to describe the quality of down, relating directly to the insulating performance. High loft down is warmer for a given weight than low loft down. Higher lofting down will fill a larger volume of space for a given weight. As a result, less down weight is required to fill each baffle in a sleeping bag. This translates to a lighter sleeping bag. The most common measure of loft is called Fill Power. 850 Fill Power implies that one ounce of this down will loft to fill a volume of 850in3. 850+ Loft Goose Down: - 850+ Fill Power (Loft) Premium Goose Down is the very best quality down available for sleeping bags. It provides the highest insulation for its weight and will last the longest.