Mens Heavyweight Merino Activewear Thermal Bottoms

High-Performance Perforated Base Layer Leggings

Designed to eliminate all cold, our Zelios men's heavyweight (278g) base layer pants are designed to deliver performance in the harshest of winter conditions.

Named after the Greek god of power, these breathable moisture-wicking and odour-resistant leggings are made from pure merino sourced from Lanerossi (Estd. 1817).

Tested on long muti-day treks in the Himalayas, and designed for extremely long durations of wear, our leggings have a perforated rear band to aid ventilation and will deliver outstanding thermo-regulation to keep you warm, and unlike synthetic alternatives, your skin dry.  Our base layer bottoms are a firm addition for all outdoor enthusiasts.

Pair with our men’s midweight merino long-sleeve top for the perfect base layer coordinated set

Please note these thermal leggings will appear sheer when worn and are not designed to be worn alone.

View more activewear products and base layers

Benefits of merino sportswear

Thermoregulating, wicking and comfortable to wear straight to skin
Naturally odour-resistant and quick drying
Lightweight and insulating protecting you from windchill
Crease-resistant fabric which holds its colour and shape
Carbon-neutral, biodegradable and sustainable

Fit notes

Black & Charcoal - Chan is 5ft 11" (180cm), Waist 32" (81cm), Inside leg 31” (79cm) and wears medium for a fitted look

True to size | Length medium 88 +/- 1cm with each size

Style summary

Thermal merino wool base layer bottoms
True to size
Heavyweight 278g knitted fabric
100% extra fine merino wool sourced from Lanerossi (Estd. 1817)
Skin-friendly, non-itch wool. Wear straight to skin
Made in our factory in India using the latest Japanese knit-ting technology
Free UK returns on orders of £100 or more
Free UK shipping on orders over £50

Wash care

Thanks to its antimicrobial properties which make it resistant to odour-producing bacteria, your merino activewear will not need to be washed as regularly. We recommend quick washes in the sink with cool water, and spot cleaning any stains. You can refresh your garment between washes by gently steaming it.

Hand wash* with gentle detergent, wool, or baby shampoo
Lay flat to dry on a towel
Apply a gentle iron with a slow steam
Do not tumble dry

*Why we use hand wash only merino wool

Machine-washable merino wool is treated with a heat-resistant plastic, which cracks as it is washed and tumble dried. Aggressive washing damages merino, causing the wool to pill more, lose its shape and appear worn quicker than caring for hand wash only fibres.

Overall, choosing hand wash only merino wool means items last longer and they’re more environmentally friendly.