Teton Bros. Hybrid InnerDenim Hybrid Inner Down XS Size: JP XS / US XXS Feels like a Japanese women's S, or a men's XS. (Used item, described as almost new, but selling because the armholes are a bit tight.) Measurements: Shoulder width: 41cm Body width: 49cm Length: 62cm Sleeve length: 56cm ※Recently, there have been cases where buyers have returned items and canceled transactions due to dirt and dust. If you need detailed photos for confirmation, please let me know in advance. Please understand that this is a used item, and those seeking perfection should refrain from purchasing. From the retailer's website: Inner down that can be used for multiple purposes in cold weather. This inner down jacket is widely used as a mid-layer in cold regions, or as loungewear in tents and mountain huts. The outer fabric is made of 12D lightweight ripstop nylon with DWR treatment, and a mix of 1000 fill power water-repellent down and synthetic fiber insulation "Thermo Max". The design balances comfort and light weight, with features like front snaps that can also be used for ventilation, and a round neck to avoid bulk when layering. It is also compact and doesn't take up much space when packed. Currently, natural down exhibits the greatest heat retention among the insulation materials available, and no material surpasses down in terms of warmth-to-weight ratio. However, down has the weakness of being vulnerable to water and moisture. When it gets wet and loses its loft, its insulation properties are also compromised. Therefore, Teton Bros. adopted "Hybrid Down". As a countermeasure against moisture, they mixed 1000 fill power water-repellent down, which has been treated with water repellency at the feather stage, with "Thermo Max", a synthetic fiber insulation that exhibits far-infrared heat storage effect. It is a high-performance insulation that is resistant to moisture while maintaining the high heat retention and light weight of down. Fabric: 12D Nylon / 1000 fill Down & Thermo Max Weight: 250g (Size M)