When hiking a steep incline, windy ridgeline, or in the pouring rain, this All-weather Activewear keeps you comfortable anytime, anywhere.

Our All-weather series, using the Pertex Shield Air, is significantly lighter than other conventional breathable moisture-permeable jackets. The fabric’s superior breathability makes the jacket unbelievably comfortable, making it work as a windshell or as a rain jacket.

The UL All-weather Jacket features a chest pocket for stowing the jacket itself and a double zipper design, achieving easy ventilation when you are pushing hard to climb a steep hill. Additionally, the snap buttons on the armholes enable quick sleeve adjustments in warmer conditions or function as thumbholes in colder weather, making it a true “All-weather” jacket.

Rainwear keeps rain out, but it also traps heat. The harder you move, the faster it gets clammy—so when the rain stops, you take it off.

Wind shells are light and breathable, but they are not built for real rain.

For years, hikers had to choose between the two: protection or breathability.

Nanofiber membranes changed that. By allowing air to pass through while keeping water out, they made it possible to create a shell that stays comfortable across changing conditions—not just when it rains.

This is not simply rainwear, and it is not simply a wind shell. It is a new category built for movement in all weather: all-weather activewear.

The chart below shows a comparison between the UL All-Weather Series and general mountaineering rainwear (assumed to be products weighing 200-300g that use breathable waterproof membranes such as Gore-Tex).

General rainwear tends to have excellent insulation, but poor breathability and a tendency to trap heat. However, the UL All-Weather Series is lightweight, highly breathable, and does not trap heat even during intense activity.

However, due to its high breathability, the UL All-Weather Series may sometimes make the wearer feel cold in strong winds. Therefore, proper layering is necessary when using it to ensure warmth.

What’s so special about the Pertex Shield Air? It’s a novel nanofiber fabric that is permeable not only by moisture but also by air. This air/moisture-permeability creates a truly unique kind of breathability.

We tested the breathability of the Pertex Shield Air of the UL All-weather series and the existing UL Rain Hoody (PU Shinsui), the Pertex Shield fabric. The test method is as follows:

The test fabric is placed in the middle of the tester. The upper half of the tester has some water in it, while the lower half is empty (filled with air). When the lower half is pressurized by the pump, the fabric lets the air pass, and bubbles are created in the upper half. The more air that passes through, the more bubbles are created. The Pertex Shield with no air-permeability does not generate air bubbles. On the other hand, the Shield Air creates many air bubbles, indicating its high air-permeability.

The large pocket added from the 2023 model, can hold snacks, maps, and other essential items for hiking. It is placed at the front where the usability of the sternum strap is not compromised.

The UL All-weather Jacket can be neatly packed in the large front pocket.

The double zipper allows it to be opened and closed from either the top or bottom for quick ventilation. This ensures you will stay comfortable in the ever-changing mountain conditions, including climbing ridges in high winds after a hard hike up.

Rainwear seams are usually sealed from the inside with seam tape, but over time, that tape can peel or weaken, creating a risk of water entering through the seams.

For the UL All-weather Jacket, we use ultrasonic welding instead. This process uses ultrasonic vibration to generate heat, melting and bonding the fabric without needle holes. It causes less damage to the fabric and helps reduce the risk of water entering through the seams after years of use.

Only a limited number of factories in Japan can perform ultrasonic welding at this level of precision. At our partner factory in Akita Prefecture, years of research and refinement have made it possible to combine the strength and waterproofness needed for hard use in the mountains.

There is a cord lock on the inside of the hood fabric that adjusts the hood. Press the cord lock and pull the cord under the hood to adjust.

Other than the double-zippered “Jacket”, the UL All-weather series includes: The zipperless ultralight “Hoody”, lengthened “Long Hoody”, zippered, pocketed, and packable “Coat”, and a pair of “Pants”. The features of each product are as follows:

• This product is an ultralight waterproof shell made with extremely thin fabric. Watch out for branches and rocks!
• To keep it performing well, you’ll need to take care of it. Sweat, dirt, and body oils mess with the fabric—wash it regularly following the care label.
• The fabric’s super thin and porous, so stuff like vaseline, bug spray, sunscreen, or anything with alcohol can stain it or mess with breathability.

Thicker fabrics tend to hold water-repellent treatments better, but the UL All-weather Series uses ultra-thin, highly breathable outer fabrics to keep things light and airy. That means while the water repellency is solid when shipped, it won’t last as long as heavier waterproof-breathable materials.

When the DWR is working, water beads up and rolls off. Once it starts to wear out, water spreads across the surface like a film, blocking breathability and making the inside feel damp or clammy.

If it feels like the water repellency is fading, toss it in the dryer or hit it with a hairdryer after washing—it’ll help bring it back. If that doesn’t do the trick, reapply a water-repellent treatment using a product from your local gear shop.

This shell is built for comfort while you’re on the move in mild conditions. It doesn’t insulate like heavier waterproof or winter shells, so when you stop or need extra warmth, make sure you’ve got the right layers.

If you’re heading into harsh environments, don’t take it lightly—plan your layering accordingly.

• Machine wash, gentle at 30°C.
• Use rainwear-specific detergent or a neutral detergent that does not contain bleaching, softening, or brightening agents.
• Wash separately or use a laundry net bag.
• Close the zipper when washing.
• Apply detergent diluted with water and wash with a soft sponge if badly stained. Do not scrub the surface joints or the seam tape on the back.
• If necessary, tumble dry the garment at a upper limit of 60°C to restore water repellency.
• Do not bleach and do not use fabric softener.
• Iron on low. Do not steam.
• Do not dry-clean.
• Vaseline, insect repellent, and ethanol-containing substances such as hair creams, cosmetics and sunscreens may stain the fabric. They may also hinder the water-permeability of the fabric. For removal methods, please refer to the our Journal; #2 – Removing stains from rainwear.

Care page

For more detailed washing, drying and water repellent care instructions, visit our SUPPORT Page. With proper care you can prolong the funtionality of the product.

• This product is an ultralight waterproof shell made with extremely thin fabric. Watch out for branches and rocks!
• To keep it performing well, you’ll need to take care of it. Sweat, dirt, and body oils mess with the fabric—wash it regularly following the care label.
• The fabric’s super thin and porous, so stuff like vaseline, bug spray, sunscreen, or anything with alcohol can stain it or mess with breathability.

Thicker fabrics tend to hold water-repellent treatments better, but the UL All-weather Series uses ultra-thin, highly breathable outer fabrics to keep things light and airy. That means while the water repellency is solid when shipped, it won’t last as long as heavier waterproof-breathable materials.

When the DWR is working, water beads up and rolls off. Once it starts to wear out, water spreads across the surface like a film, blocking breathability and making the inside feel damp or clammy.

If it feels like the water repellency is fading, toss it in the dryer or hit it with a hairdryer after washing—it’ll help bring it back. If that doesn’t do the trick, reapply a water-repellent treatment using a product from your local gear shop.

This shell is built for comfort while you’re on the move in mild conditions. It doesn’t insulate like heavier waterproof or winter shells, so when you stop or need extra warmth, make sure you’ve got the right layers.

If you’re heading into harsh environments, don’t take it lightly—plan your layering accordingly.

• Machine wash, gentle at 30°C.
• Use rainwear-specific detergent or a neutral detergent that does not contain bleaching, softening, or brightening agents.
• Wash separately or use a laundry net bag.
• Close the zipper when washing.
• Apply detergent diluted with water and wash with a soft sponge if badly stained. Do not scrub the surface joints or the seam tape on the back.
• If necessary, tumble dry the garment at a upper limit of 60°C to restore water repellency.
• Do not bleach and do not use fabric softener.
• Iron on low. Do not steam.
• Do not dry-clean.
• Vaseline, insect repellent, and ethanol-containing substances such as hair creams, cosmetics and sunscreens may stain the fabric. They may also hinder the water-permeability of the fabric. For removal methods, please refer to the our Journal; #2 – Removing stains from rainwear.

Care page

For more detailed washing, drying and water repellent care instructions, visit our SUPPORT Page. With proper care you can prolong the funtionality of the product.