The Kelvin Aerolite Jacket delivers maximum warmth with minimal bulk, even in the wettest, most extreme environments. It boasts an innovative synthetic insulation blend that replicates the low-bulk, highly compressible characteristics of down, but with warm-when-wet performance. Count on it to keep you going when temps suddenly plummet and disappear into your pack when not needed.
Against every one of the insulated jackets in the RidgeNote register with a published figure. Manufacturer-listed; sources and dates are on this page.
What fill power measures, why the 900-fill Rab Mythic Ultra weighs more than twice as much as the 850-fill Western Mountaineering QuickFlash, and how to choose between down and synthetic. A comparison of published maker specs for seven insulated jackets.
Winter warmth comes from a system: stacked pads, insulation that copes with damp, a regulated stove and traction, built from products in our catalogue.
