This down jacket is derived from the Tsurugi Jacket, which has a 10-year history. Over a decade ago, a world-renowned ice climber formerly of the NATO mountain troops, and a gentleman from the SAS who was devoted to critical mountaineering, along with a third person, launched the "Mountain Project" to develop systematically wearable clothing, from base layers to shells and over-jackets. The main shell of that project is the current "Tsurugi Jacket." The ventilation system common to all is arranged from the system and angle of the TB Jacket & Pant. The Tsurugi 10th Down Jacket has been updated with an insulation shape designed for relatively low-temperature situations, and is filled with 850 fill power down with water-repellent treatment. Length 78 / Width 62 / Sleeve Length 94