The air is leaking. Purchased in 2022. Product number: #1124660 Montbell U.L. Comfort System Alpine Pad 25 150 This model is perfect for mountaineering, achieving outstanding lightness and compactness. By adopting a unique mummy shape, it achieves both outstanding lightness, compactness, and comfort. It is compatible with various mountaineering styles. Specifications [Material] Surface: 30-denier polyester ripstop [TPU laminate] Cushioning: Urethane foam [Weight] 556g (571g) *The figures in parentheses ( ) include the stuff sack.