Spark Sp III Down Sleeping Bag - Long -8C

Ultralight, High-Performance Down Sleeping Bag.

The Sea to Summit Spark SP III is engineered for ultralight backpackers and alpine adventurers who demand maximum warmth with minimal weight and bulk. Rated to 25°F (-4°C), it features 850+ fill power RDS-certified goose down treated with non-PFAS Ultra-Dry Down™, ensuring reliable insulation even in damp conditions. The 10D nylon shell and liner fabrics keep weight low while offering breathability and durability. A contoured mummy shape, technical hood, and draft tube enhance thermal efficiency, and the 1/3-length YKK zipper minimizes weight without sacrificing functionality. Weighing approximately 22 oz (625g) and compressing to a remarkably small volume, the Spark SP III is ideal for three-season use where every ounce counts.