Darn Tough Mountaineering Over-the-Calf Heavyweight M’s

Darn Tough Mountaineering Over-the-Calf Heavyweight M’s

The warmest sock from Darn Tough for winter trekking and mountaineering. With these, you can count on having the best cold-weather sock on the market.

The moment you hold a pair of Darn Tough Mountaineering socks, you’ll notice the quality—they’re unlike your typical long sock. Crafted from a dense, resilient blend of merino wool and nylon, these socks feel substantial and built to last. They extend over the calf and stay firmly in place without slipping.

Measuring approximately 43 cm from heel to top, the Mountaineering socks keep your lower leg’s circulation warm, right up to just below the knee. Designed for a snug, performance fit, they won’t slide, bunch up, or cause friction, making them ideal for demanding hikes.

Merino wool is unbeatable in cold conditions: it efficiently wicks moisture from the skin, keeping feet fresh and dry. These are the warmest Darn Tough socks—thick to retain heat, wick moisture away, and provide steady comfort in even the coldest adventures.

These socks are fully cushioned with terry loops throughout, offering maximum warmth, flexibility, and comfort.

Materials: 73% merino wool, 25% nylon, 2% Lycra

Our tips: With high thread density, the fabric is initially dense and form-fitting. If you’re between sizes, we recommend choosing the larger size. The excellent fit prevents blisters from forming and keeps the sock from slipping below the calf.

The merino wool is mulesing-free (certified by the Responsible Wool Standard) and pre-shrunk, so they won’t shrink with washing. Excess material from the Darn Tough factory is recycled into fire blankets and airplane seat padding.

Care instructions: Machine wash in warm water, turning socks inside out on a gentle cycle. Avoid bleach. Tumble dry low or air dry. For daily use, we find the socks stay fresh for multiple days, thanks to wool’s natural properties, saving you from frequent washing and helping the environment. Even if your feet get a bit warm, the wool keeps them comfortable.

About the warranty: If a sock develops a defect or hole, Darn Tough’s warranty has you covered. The warranty, naturally, doesn’t apply if the sock was burned by a campfire, chewed by a dog, or spirited away by the laundry gremlins. And if the sock truly reaches the end of its life, perhaps it’s time to send it off to the recycling bin with a respectful farewell. This way, prices stay fair for the rest of us.

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