Inspired by the classic US Navy deck jackets of the 1940s, our interpretation of the N1 has become a signature piece for Iron Heart—and for Fall/Winter ’25, we’ve expanded the lineup with a new lightweight model. To achieve this, we’ve replaced the heavy wool insulation and quilted sleeves with a much lighter water-resistant Japanese Ventile cotton lining, slimming the jacket down, enhancing breathability and for a layer of protection against wind and rain. Another key difference between this lightweight jacket and our heavyweight models is the fabric used in construction. While this model is still cut from a tough 12oz whipcord, the yarns of this particular “jungle cloth” are dyed using sulphur dye. Unlike the fade-resistant reactive-dyed whipcord used for our traditional N1, this fabric is designed to fade with wear and washing, evolving with vintage charm to complement the WWII-era cut. Finished with a corduroy-lined collar that contrasts the whipcord, the result is a jacket that offers classic N1 styling at the perfect weight for the transitioning seasons. [SIZE-GUIDE-INCH] Tag Size XS S M L XL XXL XXXL XXXXL Shoulders 16.8 17.1 18.0 19.0 19.6 20.4 21.1 22.1 Length 25.1 25.1 25.8 26.5 27.4 28.1 28.9 29.8 Chest (P2P) 22.1 22.4 23.1 24.1 24.6 25.5 26.3 27.1 Waist 21.1 21.5 22.3 23.1 23.6 24.6 25.3 26.0 Opening 20.5 21.0 21.9 22.7 23.3 24.1 24.8 25.1 Sleeve 23.6 23.8 24.1 24.9 25.4 25.9 26.5 27.3 Sleeve Opening 4.7 4.8 4.8 4.9 5.0 5.1 5.2 5.2 [SIZE-GUIDE-CM] Tag Size XS S M L XL XXL XXXL XXXXL Shoulders 42.7 43.4 45.7 48.3 49.9 51.7 53.7 56.0 Length 63.6 63.8 65.4 67.3 69.5 71.5 73.5 75.6 Chest (P2P) 56.3 56.9 58.8 61.1 62.4 64.8 66.8 68.7 Waist 53.6 54.6 56.6 58.5 59.9 62.5 64.1 66.0 Opening 52.1 53.3 55.8 57.7 59.1 61.3 63.0 63.9 Sleeve 59.8 60.3 61.1 63.1 64.5 65.9 67.2 69.2 Sleeve Opening 11.8 12.2 12.3 12.4 12.6 13.0 13.1 13.2