W-Series Waterproof Shell Pants

When conditions get tough, you need maximum protection, and that is where the W-Series Waterproof Shell Pants will help you bring out your best. These are technical, lightweight 3-layer waterproof/breathable pants designed for FAST&LIGHT mountaineering. Crafted with the eVent® DVStorm™ 3-layer membrane, they offer exceptional protection with a 20,000 mm water column waterproof rating and 30,000 g/m²/24h MVTR breathability, keeping you dry and comfortable during high-intensity activities.

They feature a wide YKK™ AquaGuard® waterproof side zipper with double sliders to allow quick access with boots and to ventilate the leg when activity is very intense.

Key features include fully taped seams and a super resistant lower fabric with Kevlar. Their ultralight construction and excellent weather protection make the W-Series Waterproof Shell Pants ideal for FAST&LIGHT activities. Combine them with other garments from the W-Series collection (ideal over the W-Series Meteor Insulated pants) and discover the lightest and most functional way to move in the mountains.

FAST&LIGHT - 317 g. (S)

Equipment

Full side zippers with double YKK™ AquaGuard® sliders

Highly resistant lower fabric against cuts

Waterproof YKK™ zipper fly with easy-grip puller

Elastic waistband with elastic band and pull tab

Pre-shaped knees

Elastic band to pass under the boot (adjustable and replaceable) to prevent the pant from riding up

Top Layer Fit: designed cut to be worn as a third layer

Weight

Size S: 317 grams

Size M: 333 grams

Size L: 351 grams

Size XL: 368 grams

Fabric

eVent® DVStorm™ 3-Layer

Waterproof, breathable, and 100% windproof. 100% nylon fabric, 20 deniers, 90g/m².

Waterproofness: 20,000mm water column (ISO811) | Breathability: 30,000g/(m²·24h) (JIS L 1099 B2).

Air permeability: 0.207 cfm (ASTM D737). DWR (PFC Free) treatment repels rain and snow, protecting the membrane from water saturation and enhancing breathability.

Note: Avoid using deodorants, makeup, or sunscreen in direct contact with the membrane, as these can contaminate it and cause irreversible damage.

Technology

The main difference between eVent® DVStorm technology and other waterproof/breathable fabrics on the market lies in the billions of microscopic pores embedded in our proprietary membrane. These pores begin to work instantly as the sweat vapor generated by physical activity starts to accumulate inside your clothing or footwear.

This technology is called Direct Ventilation, and unlike other technologies, it doesn’t require any external activation to begin breathing. It is a “dry” system that allows eVent membranes to be fully waterproof and breathable, keeping you dry and comfortable across a wide range of temperatures and conditions.

OS2O is the pioneering brand in Spain using eVent® membranes.

Sizes