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Heatwave Thermalwear

Heatwave® Men's Thermal Trousers Long Johns Pack of 2 Durable Warm Baselayer Underwear for Cold Weather Running Hiking Active Outdoor Sports and Workwear Available in Black Grey Navy White Sizes Small to XXL

Regular price £10.00 GBP
Regular price Sale price £10.00 GBP
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Heatwave® Pack Of 2 Men's Thermal Trousers Long Johns

The Heatwave® Pack Of 2 Men's Thermal Trousers Long Johns is designed to be your ultimate companion for cold weather. These durable and warm underwear baselayers are perfect for active outdoor activities such as running, hiking, and sports. What sets these thermal long johns apart is their advanced insulating technology and comfort-driven design, making them a must-have for anyone looking to stay warm and comfortable during chilly conditions.

Key Feature 1: Advanced Insulating Yarn

Description: These thermal trousers boast a 0.45 tog rating, which means they hold more warm air close to the skin. The inner layer is soft-brushed, made from advanced insulating yarn that offers high performance insulation.

Benefits: The advanced insulating yarn provides exceptional warmth, making these long johns ideal for extremely cold weather. This feature is particularly beneficial for outdoor enthusiasts and those working in cold environments.

Key Feature 2: Comfort Fit

Description: The ribbed construction of these thermal trousers shapes to the contours of your body, providing a comfort fit that is both snug and flexible. The design also includes an open fly for added convenience.

Benefits: The comfort fit ensures that the long johns move with you, providing unrestricted mobility during physical activities. The open fly adds an extra layer of convenience, especially for those on the go.

Key Feature 3: Versatile Material Blend

Description: Made from a 50% polyester and 50% cotton blend, these thermal trousers offer a balanced mix of durability and comfort. The material is designed to withstand regular wear and tear while maintaining softness.

Benefits: The material blend ensures longevity and comfort, making these long johns a practical choice for daily wear. The durability of the fabric is particularly useful for those who engage in active or demanding outdoor activities.


  • Small - Long John (Waist Size) 29-32”
  • Medium - Long John (Waist Size) 33-35”
  • Large - Long John (Waist Size) 36-38”
  • X-Large - Long John (Waist Size) 39-42”
  • XX-Large - Long John (Waist Size) 43-45”

*All sizes are approximate

Colours Or Style Options

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

Care Guide

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

Why Choose This Product

The Heatwave® Men's Thermal Trousers Long Johns are a superior choice for anyone looking to stay warm and comfortable in cold conditions. With advanced insulating yarn, a comfortable fit, and a durable material blend, these long johns are designed to offer maximum performance. Don't just take our word for it; our customers have praised the exceptional warmth and comfort these thermal trousers provide. Choose Heatwave® for quality, reliability, and unmatched value.

Additional Information

Usability: Perfect for a variety of activities including outdoor running, hiking, sports, and even as workwear. These thermal trousers are versatile enough to be used in numerous real-life scenarios where warmth and comfort are essential.

Warranty and Support: Comes with a satisfaction guarantee. Customer support is available for any queries or issues, and return policies are in place to ensure you are completely satisfied with your purchase.


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 33 reviews
Alison Johnson (Llanrwst, GB)
Long johns

As described,good quality



Angie Jordan (Tower Hamlets, GB)
My husband loves them

Comfortable and keeps you very warm

Lynn Fuller (Southwark, GB)

A it thinner than I thought they would be. But okay

Julie Macdonald (Rhyl, GB)
Amazing service

From ordering to receiving was so quick this service was 10/10 thank you so much

Chris Holroyd (Manchester, GB)
Awesome Thermal Bottoms

Awesome thermal bottoms great feel and material, nice and comfy.

Katherine Simpson (Whitchurch, GB)
2 Pack Heatwave Thermal Long Johns

Very quick delivery, my Son is delight with them travelling to and from work in the cold weather, fit very well.

David Meeks (Chester-le-Street, GB)
Gd quality thermals

Good quality and very reasonable price and quick delivery


Great value for great price

Anonymous (Conwy, GB)

Great purchase