Thermoactive La Sportiva Wool40 Longsleeve

Cold-weather layering often forces a choice between warmth and breathability, but the La Sportiva Thermoactive Wool40 Longsleeve eliminates that compromise. This men's base layer top blends the natural insulation and odor resistance of merino wool with the durability and moisture management of polyester, keeping you comfortable during high-output activities in cool to cold conditions.

Who is it for

Mountaineers, hikers, skiers, and trail runners who need a versatile midweight base layer that performs across seasons. The slim, ergonomic fit and 4-way stretch make it ideal for active pursuits where unrestricted movement and reliable thermal regulation are essential.

Main features

• Thermoactive fabric with approximately 40% mulesing-free merino wool and 60% polyester for balanced warmth, wicking, and quick drying.
• Midweight construction (180–200 g/m²) provides excellent warmth-to-weight ratio for all-season layering.
• Natural anti-odor properties of merino wool keep you fresh during multi-day adventures.
• Flatlock seams reduce chafing and enhance comfort under pack straps or harnesses.
• 4-way stretch fabric moves with you, while the crew neck and long sleeves offer classic coverage.

Specifications

• Product Type: Base Layer Top
• Gender: Men's
• Sleeve Length: Long Sleeve
• Neckline: Crew Neck
• Material: 40% Merino Wool, 60% Polyester
• Fabric Weight: Midweight (180–200 g/m²)
• Fit: Slim, Ergonomic
• Seams: Flatlock
• Stretch: 4-way
• Breathable: Yes
• Fast Drying: Yes
• Thermal Insulation: Yes
• Odor Resistance: Natural (Merino)
• Recommended Use: Mountaineering, Hiking, Skiing, Trail Running, Outdoor Activities
• Season: All-season layering
• Sustainability: Mulesing-free Merino wool
• Care Instructions: Machine wash cold, do not bleach, tumble dry low, do not iron, do not dry clean

Tips

For optimal performance, layer this top under a softshell or hardshell jacket in colder conditions. The merino wool naturally regulates temperature, so you can wear it comfortably across a wide range of temperatures. Avoid fabric softeners to maintain the wool's natural properties.