What Our Gearhead(R) Experts Are Saying:"I've been wearing the Nano Puff for years, and this updated version is even better. It's warm for its weight, crazy packable, and super versatile, so I use it as my main layer for shoulder seasons or as insulation under a shell when things get cold."Lightweight, windproof, and always ready for adventure, the Nano Puff Hoodie is one of our favorite layering pieces for year-round mountain missions. With 60g of PrimaLoft(R) Gold Insulation Eco packed into a recycled polyester ripstop shell, this jacket delivers reliable warmth even when wet-all while keeping bulk and weight to a minimum. Its compressible design stows easily into its own pocket, making it a go-to for tossing in our pack no matter the forecast. A water-repellent finish sheds light moisture, while the elastic-bound hood and cuffs help lock in heat.