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Heatwave Thermalwear

Heatwave® Pack Of 2 Men's Thermal Underwear Set T-Shirt & Pants Set Durable Warm Underwear Baselayer Active Outdoor Running Hiking Winter Sportswear Workwear Black Grey Navy White Small Medium Large Comfortable Insulating Yarn Seam-Free Design

Regular price £18.00 GBP
Regular price Sale price £18.00 GBP
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Heatwave® Pack Of 2 Men's Thermal Underwear Set

Discover the ultimate in warmth and comfort with the Heatwave® Pack Of 2 Men's Thermal Underwear Set. Perfectly designed for active outdoor pursuits like running, hiking, and various sports, this set includes both a T-shirt and pants, making it an essential baselayer for your cold-weather wardrobe. Available in multiple colors and sizes, it stands out for its exceptional insulation and comfort fit, positioning it well ahead of its competitors.

Key Feature 1: Advanced Insulating Yarn

Description: The thermal underwear is crafted from an advanced insulating yarn that offers a 0.45 tog rating. This high-performance material is designed to hold more warm air close to the skin, ensuring maximum insulation and warmth.


  • Stay warm even in the coldest conditions, making it ideal for outdoor activities and workwear.
  • The advanced yarn helps to enhance your overall comfort by maintaining body heat.

Key Feature 2: Soft Brushed Inner

Description: The inner layer of the thermal underwear is soft brushed, providing an extra layer of comfort against the skin. The ribbed construction shapes to the contours of your body for a snug fit.


  • Enjoy a cozy and comfortable experience, reducing any irritation or discomfort.
  • The snug fit keeps the thermal underwear in place, allowing for better movement and flexibility.

Key Feature 3: Seam-Free Design

Description: The tops are designed to be side seam-free, enhancing comfort and reducing potential chafing. The long johns come with an open fly for added convenience.


  • The seamless design ensures a smoother fit, making it perfect for layering under other clothing.
  • The open fly adds practicality, especially during outdoor activities.


  • Small: Top (Chest Size) 34-36” : Long John (Waist Size) 29-32”
  • Medium: Top (Chest Size) 37-39” : Long John (Waist Size) 33-35”
  • Large: Top (Chest Size) 40-42” : Long John (Waist Size) 36-38”
  • X-Large: Top (Chest Size) 43-45” : Long John (Waist Size) 39-42"
  • XX-Large: Top (Chest Size) 46-48” : Long John (Waist Size) 43-45”

Colours Or Style Options

  • White
  • Blue
  • Charcoal
  • Black
  • Navy
  • Grey

Care Guide

  • Machine washable at 40°C
  • Can be tumble dried
  • Wash dark colors separately

Why Choose This Product

The Heatwave® Men's Thermal Underwear Set is a superior choice for those seeking reliable warmth and comfort. With its advanced insulating yarn, soft brushed inner, and seam-free design, this set offers unparalleled benefits for outdoor activities and everyday wear. Don't just take our word for it—our users rave about the exceptional warmth and fit. Choose Heatwave® for quality, value, and the assurance of staying warm in any conditions.

Additional Information

Usability: Ideal for a variety of scenarios, from outdoor sports and hiking to daily workwear. The versatile design makes it suitable for layering, ensuring you stay warm in multiple settings.

Warranty and Support: Enjoy peace of mind with our comprehensive warranty and excellent customer support. We offer hassle-free returns to ensure your complete satisfaction.


We have partnered with 20 innovative grassroot companies that we believe can help reverse climate change. We allocate a fixed margin from every sale to support fund nature-based carbon removal solutions such as reforestation and soil carbon sequestration. Fund companies such as DroneSeed, Grassroots Carbon, and Pachama.

We are committed at Sock Stack to neutralize our shipping emissions and remove carbon dioxide from the atmosphere. Learn more here.

We also work closely with Royal Mail to ensure hassle-free, on-time delivery. Generally processing times are within 1 business day*. Processing times may also be extended during holidays, launches/re-stocks, limited edition releases and promotions. We will notify you as soon as your order ships or if we foresee any issues with fulfilling your order. Read our full Shipping Policy for more information.
*Please understand that business days do not include weekends and Bank Holidays (United Kingdom).

£3.95 flat fee for all domestic within the United Kingdom (free shipping over £40), 2-4 working days.
£5.95 express fee for all domestic within the United Kingdom, 1-3 working days.

Easy returns

Not completely satisfied with your purchase? Reach out within 35 days to explore hassle-free return options. We've simplified cancelations for a full refund and additionally return requests can be made from your online account. Please review our Refund Policy for more details. Thank you for your patience and understanding as we navigate this together.


Sock Stack does not have a call centre and we're not set up to handle high volumes of phone calls.

The Sock Stack brand was built online, including our customer support. Though you may receive an automated response every once in a while, all channels are manned by human staff who are eager to help you out, quickly and efficiently.

Thank you again for visiting Sock Stack. For information on our new product launches, please follow us on Instagram & Facebook. For customer service inquiries, please send us a message on Facebook Messenger or e-mail us at For order inquiries, please include your order number for faster service.


Clearpay makes budgeting easier, allowing you to break down your payments into four installments, due every two weeks, interest free. Head over to Sock Stack and find something you love. Then, just add to bag and simply select Clearpay as your payment method at the checkout. Enjoy your new stuff right away and pay over four installments.

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Buy now and pay 30 days later with KLARNA payment portal. You get all the “closure” of a full upfront payment, but with the cash-flow benefits of spreading the cost. The total amount charged to your card is no greater than if you simply paid for the entire purchase up front.



We are a young, bold homeware brand. We’re fun, we’re social and we’re an upcoming brand that doesn’t sleep. Interested in partnering? Apply today to be part of our community.

Sock Stack

Our Mission

Heatwave Thermalwear® envisions becoming the most celebrated, trustworthy, and sought-after brand by offering superior, distinctive, and inexpensive thermal wear products that exceed every customer's expectations. Heatwave Thermalwear's® vision is to become a leading thermal underwear baselayer brand by delivering the most refined and high-grade products to the customers that are thoughtfully developed to withstand extremely cold conditions while offering enhanced protection and unmatched comfort.

Sock Stack

Function, Fit & Style

Heatwave Thermalwear® strives to provide a diverse collection of the highest quality and affordable thermal underwear to men and women. Our thermal socks, long-sleeve base layers, long johns, hats and gloves are meticulously designed to be safe, lightweight, and breathable, providing fast-wicking and added warmth. As a customer-first brand, we are committed to fostering solid and lifelong relationships with our clients and aspire to deliver exceptional quality and value in our products.

Customer Reviews

Based on 25 reviews

Bought as Xmas gifts. Quality very good


Bought as Xmas presents so cannot really comment but quality looks very good.

Anonymous (Nottingham, GB)
Great buy

These were a brilliant price more so for 2 sets in a pack, I wasn’t holding my breathe as at that price for 2 sets I didn’t think would be as good as they are, very cozy & wash well, have a very happy warm husband

Pam Kelham (Southampton, GB)

Very good


Good Value for money 💰


Good Value for money 💰

tom wilkins (Bedford, GB)
Heatwave® Pack Of 2 Men's Thermal Underwear Set, T-Shirt & Pants Baselayer Set

Really pleased with this item. A decent amount of thickness to the clothing and a nice subtle vertical stripe or rib pattern on them. Plain, simple, good quality, better than I expected for the price point.

Pashar Chikanya

Heatwave® Pack Of 2 Men's Thermal Underwear Set, T-Shirt & Pants Baselayer Set

Sharen Campbell (Tollesbury, GB)
Thermal mens wear

All good


Good product delivered swiftly