Juniors Merino Wool Base Layer Set – Helly Hansen LIFA® – Midweight Thermal

Cold-weather adventures start with a comfortable first layer. The Helly Hansen Kids’ LIFA® Merino Midweight Base Layer Set includes a long-sleeve thermal top and matching bottoms, giving kids a warm, moisture-managing foundation for outdoor school, skiing, sledding, hiking, winter travel, and everyday outdoor play.

Helly Hansen’s two-layer LIFA® Merino construction pairs moisture-moving LIFA® fibers next to the skin with breathable Merino wool on the outside. As kids run, climb, build snow forts, and explore, the inner layer helps move perspiration outward while the wool provides insulating warmth and helps regulate temperature. When the pace slows for snack time, the ride home, or a quiet moment outside, Merino wool continues to insulate when damp.

Midweight warmth, flatlock seams, and a streamlined layering fit make this an easy foundation beneath fleece, snow gear, rainwear, and winter outerwear. It is the kind of practical layer that earns a regular place in the cold-weather gear drawer—made for active kids and the winter days they will remember.

Why Parents Love It

• A complete cold-weather base layer: Includes both a long-sleeve thermal top and matching bottoms, making it easy to build a comfortable first layer from head to toe.
• Manages moisture while kids move: The LIFA® inner layer helps move perspiration away from the skin during active outdoor play.
• Warmth without unnecessary bulk: Midweight construction provides dependable insulation while layering comfortably beneath fleece and outerwear.
• Made for changing activity levels: Breathable Merino wool helps regulate temperature and continues to provide insulation when damp.
• Comfortable under outdoor gear: Flatlock seams help create a smoother feel beneath snow pants, rainwear, fleece, and winter jackets.
• Useful far beyond outdoor school: Reach for it for skiing, sledding, hiking, camping, winter travel, recess, and everyday cold-weather adventures.

Built for Real Outdoor Use

Kids rarely spend a winter day moving at one steady pace. They race up hills, pull sleds, climb through snowbanks, stop to investigate something interesting, and eventually settle down for a snack or the ride home.

That changing rhythm is where a thoughtfully designed base layer matters. LIFA® fibers help manage moisture during high-energy play, while the Merino wool outer layer adds breathable insulation for cold conditions. Together, they create a practical first layer designed to help kids stay comfortable through the movement, pauses, and changing pace of a real day outside.

The close-to-body, midweight design also leaves room for the rest of a flexible winter layering system. Add fleece or another insulating midlayer when conditions call for more warmth, then finish with weather-protective outerwear appropriate for the day.

Things to Know

• Midweight base layer: Designed to provide more warmth than a lightweight first layer while remaining easy to wear beneath additional insulation and outerwear.
• Two-piece set: Includes one long-sleeve base layer top and one pair of matching thermal bottoms.
• Not 100% Merino: The fabric is 57% Merino wool and 43% polypropylene, combining wool insulation with LIFA® moisture management.
• Wear next to the skin: Wearing the set as the first layer allows the LIFA® inner layer to do its moisture-moving job.
• Close-to-body fit: Base layers work best when they fit close enough to manage moisture without restricting movement. Helly Hansen reports that customers generally find this set true to size; check the current size chart when choosing a size.
• Layer for the conditions: Add insulating and weather-protective layers based on temperature, wind, rain, snow, and activity level.

Product Details

• Includes: Long-sleeve thermal base layer top and matching bottoms
• Material: 57% Merino wool, 43% polypropylene
• Construction: Two-layer LIFA® Merino
• Weight category: Midweight
• Moisture management: LIFA® polypropylene inner layer helps move perspiration away from the skin
• Insulation: Merino wool outer layer provides breathable warmth and continues insulating when damp
• Seams: Flatlock seams
• Waist: Elastic waistband
• Manufacturer-listed weight: Approximately 250 g
• Additional details: LIFA® stripe detailing and discrete logo tab
• Wool: ZQ-certified
• Main fabric: Solution dyed
• Manufacturer product number: 49403

Why ODSS Recommends It

A good winter layering system begins before the fleece, snow pants, or jacket goes on. For active kids, that first layer needs to handle movement and moisture while providing comfortable warmth without adding unnecessary bulk.

We like the Helly Hansen LIFA® Merino Midweight Set because its two-layer construction gives each material a clear job: LIFA® helps move moisture away from the skin, while Merino wool provides breathable insulation. And because the top and bottoms come together as one set, getting dressed for a cold morning is a little more straightforward.

From outdoor-school mornings and snowy playgrounds to ski weekends, winter hikes, and backyard adventures, it is a versatile foundation for a practical outdoor childhood—made for muddy boots, rosy cheeks, snow-covered mittens, and staying outside just a little longer.

Washing Instructions: Use wool detergent. Wash inside out. Do not wring.

Materials: 57% Merino wool, 43% polypropylene

Country of Origin: Imported

Style No: #49403