Radical 8ZWinter sleeping bag (–10°C)

Radical 8Z is a sleeping bag built for places few have dared to go.

We designed it for winter bivouacs, long traverses, and high-altitude expeditions – for those who don’t look for warm hotels but for silence, snow, and mornings with a view of the peaks. And who knows that in the mountains, comfort is something you have to bring with you.

It’s filled with 630 grams of Polish White Goose down with a fill power of 900 CUIN. That’s what gives you warmth the moment you slip inside. The down expands instantly, creating an insulating layer of air that lets you sleep comfortably at –2°C, safely at –10°C, and protects you in extreme situations down to –25°C.

The down is arranged in Z-shaped baffles. In this model, we used a double-layer construction with an 8 cm loft, which distributes the fill evenly and minimizes the risk of cold spots. Additional protection comes from the IRL – Infrared Reflective Layer, which reflects heat back toward your body. It helps the bag warm up faster and keeps the warmth inside longer.

During long nights, staying dry is just as important as staying warm. That’s why we used our HMS – Humidity Management System. It protects the down from moisture and helps release it to the outside. In the hood, where breath tends to condense, and in the foot section, which often touches the tent walls, we added special panels made of water-resistant fabric. Thanks to them, the sleeping bag retains its insulating properties for longer.

We also focused on comfort. The hood has an anatomical shape with an adjustable face opening you can tighten with one hand, even while wearing gloves or lying inside the bag. The 3D shoulder collar wraps around your shoulders and traps warmth where it escapes the fastest. The mummy-shaped design helps heat the interior quickly and makes rest and recovery easier.

On the outside, the Radical 8Z is protected by GELANOTS Ultra Light Rip Stop Shell – an ultralight, technical fabric resistant to wind, snow, and abrasion. It doesn’t absorb water, doesn’t tear on contact with rock, and allows the down to perform at its best. In areas exposed to moisture – around the head and feet – we used additional waterproof panels.

The bag features a two-way YKK zipper with an asymmetrical design that relieves pressure on the shoulder and allows temperature regulation from both ends. It runs smoothly even in gloves, and the insulated flap prevents heat loss.

After a night out, you can hang it to dry using internal or external loops. Inside, you’ll find a practical pocket for essentials like chemical warmers, a headlamp, or your phone.

The Radical 8Z weighs 1030 grams and packs down to just 6 liters. It comes with two bags – a compression sack for travel and a mesh storage bag for off-season use. One for the road, and one for after it.