The Smartwool Outdoor Merino Base Layer Men’s Thermal Bottoms are engineered to deliver premium comfort and high-performance utility across all seasons. Designed as a versatile wool/synthetic blend, these thermal bottoms combine Merino wool with COOLMAX EcoMade technology to achieve the ultimate balance of natural properties and technical performance. The natural properties of Merino ensure exceptional temperature regulation and inherent odour resistance, making them perfect for multi-day backcountry trips, while the engineered COOLMAX fibres optimise breathability and rapid moisture evacuation during high-exertion activities. Built for rugged environments, the hybrid construction enhances overall fabric durability, resisting wear and tear much better than pure wool alone. Every physical detail is optimised for an active lifestyle, featuring smooth flatlock seams and flexible merrow stretch stitching that effectively eliminate chafing under heavy gear or a backpack harness. Boasting a modern slim fit, they stay close to the skin to efficiently wick sweat away, anchored securely by a wide elastic waistband that distributes pressure evenly for long-term comfort. A functional fly adds practical convenience, establishing these bottoms as an indispensable baseline asset for hiking, skiing, running, or any cold-weather tactical layering system.

Key Features:

  • Premium Hybrid Blend: Features an innovative wool/synthetic blend utilising 50% Merino wool for natural warmth and 50% COOLMAX EcoMade recycled fibres for lightning-fast dry times.
  • Climate and Odour Control: Provides natural temperature regulation to keep you comfortable in all seasons, alongside natural odour resistance that keeps the garment fresh during extended use.
  • Advanced Moisture Management: Engineered for superior breathability to quickly pull sweat away from the body during intense outdoor workouts.
  • Rugged Longevity: The integration of technical synthetics elevates the fabric's durability, ensuring the garment holds up against heavy friction and repeated washing.
  • Chafe-Free Construction: Constructed with low-profile flatlock seams and highly flexible merrow stretch stitching to prevent skin irritation when moving.
  • Athletic Ergonomics: Designed with an active slim fit, a secure and comfortable wide elastic waistband, and a highly practical functional fly for seamless daily usability.
Yes, they should fit snugly like second skin without restriction of movement. A close fit is necessary for the moisture-wicking property to work efficiently and provide temperature regulation.
If washed properly, it should retain its shape and size. Air dry them flat on a clean towel, or select the lowest heat and tumble dry settings. It is advisable to avoid extreme heat and harsh agitation to the prevent the wool fibres from felting. Fabric softeners and bleach may also permanently damage the wool fibres.

Brand : Smartwool

SKU: SMWL-SW003094

Model # : SW003094

Gender : Mens

Clothing Type : Bottoms

Materials : 50% Merino Wool | 50% COOLMAX EcoMade Recycled Polyester

Free shipping on orders over $140 to Australia*
Shipping on small orders (under $140) only $9.95
Shipping on all orders to NZ only $9.95
Express shipping to Australia & NZ only $15

Standard Shipping (AU) – FREE on orders over $140 and $9.95 on orders under $140. Orders are dispatched within 1 business day. Click here for shipping delivery times

Select ‘Standard Shipping – Auspost Only’ if you would prefer your parcel is sent with Auspost. Otherwise it will be shipped with any of our available carriers. Auspost Only shipping is not available on some very heavy/bulky orders.

Express Shipping (AU/NZ) – Need it faster? Express Shipping is available for $15. Express Shipping is not available on heavy/bulky orders. Orders placed before midday on business days are usually dispatched same day (otherwise within 1 business day). Delivery times in the table below.

Click and Collect – Shop online and collect in our Milton, Brisbane store, free for all orders. Orders are usually ready within 2 hours (during opening hours). Click here for address and opening hours.

Terms and conditions apply, click here for a full overview of our shipping policies

  • If you have selected the wrong product/size for you, or want to exchange/return for any reason except for warranty or our error, this is referred to as a 'change of mind' return.
  • Not all products are eligible for change of mind returns (click here for excluded products).
  • Once you submit a Return Request, we will provide return instructions via email (along with a prepaid return label if applicable). Please wait to receive this before returning any items (Try 2 Anything excluded)
  • Change of mind returns can be resolved by your choice of exchange, full store credit, or a refund. Refunds are subject to a $19.95 admin fee.

For a full overview of our returns and warranty policies, see Returns and Warranties

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