Filled with 850+ Loft Ultra-Dry Down and surrounded by 3D NanoShell, an Alpine Series sleeping bag is your cocoon in the high mountains or the Arctic. The mummy-shaped cut and anatomically shaped foot box keeps warmth close to the body without constricting. The enlarged neckline and the close-fitting hood ensure that the cold air is kept out and heat loss around the face is minimized. The oversized zipper channel features the lightest and stiffest anti-snag material, making it super easy to put on and take off. The safety pocket inside the sleeping bag is easily accessible, making it ideal for storing electronic devices to keep the batteries working longer in extreme cold.
In the Alpine series, the separate down chambers are filled with 60/40 feathers, so there is more down on the top of the sleeping bag for maximum insulation. The soft inner fabric does not let any feathers through, is highly breathable and guarantees a comfortable sleep. The Alpine series is recommended for expeditions, mountain routes in the Andes, high mountain climbing in the Himalayas and winter tours in New Zealand.
The mummy-shaped Alpine sleeping bags are equipped with a hood, widened shoulder area and a larger torso area to accommodate several layers of clothing underneath in extreme weather conditions. Increased clearance around the knees increases comfort when turning a lot while sleeping. The oversized foot box has room for a pair of boot liners.
The Ultra-Dry Down water-repellent treatment protects down from external moisture and internal condensation. Ultra-Dry Down is a permanent nano-level, water-repellent synthetic treatment, with which the very airy, high quality down is treated. The nano-level treatment significantly improves the down's reaction to water without affecting weight or volume. Compared to untreated down, Ultra-Dry Down retains over 60 % more filling power and absorbs 30 % less moisture. The nano-level treatment also inhibits bacterial and microbiological growth, making Sea to Summit sleeping bags more hygienic and extending their life span.