This bivy uses AscentShell™, a three-layer waterproof and breathable fabric, which effectively blocks rain and wind from the outside while allowing internal moisture (sweat and exhaled water vapor) to escape. In other words, it's a bivy that achieves "tent-like livability" in an ultra-lightweight and compact package. This model is especially recommended for UL (ultra-light) hikers and backpackers who want to lighten their load. Basic Specifications - Seasons: 4-season - Material: AscentShell™ (3-layer waterproof breathable fabric) - Floor: 40-denier ripstop nylon (TPU laminate) - Weight: Approximately 650 g (including the included pole. Weight can be reduced by removing the pole) - Length: Approximately 82 inches (approx. 208 cm) - Packed Size: About the size of a 1L bottle (very compact) - Features/Functions - Hoop pole at the head provides space around the face → Improves breathing and ventilation - Side entry design for easy entry/exit and access to gear - Sombrero flap + zipper protects the seated position and blocks rain and wind - Independent opening and closing mosquito net (convenient for stargazing or during insect-heavy seasons) Frequency of Use/Condition Used a few times as an emergency bivy and then stored at home. Overall in good condition. However, there are small bubbles due to hydrolysis on some thin seams (this is a cosmetic deterioration, and we have not confirmed any significant decrease in waterproof performance at present, but please understand this as a used item).