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Press Releases

Seirus Introduces HeatWave™ Base Layer LITE

Brings Ultra-Thin Four-Season Comfort for Changing Conditions

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SAN DIEGO, CA – The success of Seirus’ HeatWave™ Base Layers has led to demand for a four-season option providing silky soft comfort and thermoregulation for any activity. Leveraging more than 30 years of innovation and forward-thinking design, the new Heat Wave Base Layer LITE offers a breathable, wafer thin combination of Seirus’ proprietary HeatWave™ fabric with added wicking and ventilating fabrics for all-day, everyday comfort and quality. 

Making comfort and protection a staple of their designs since 1984, Seirus’ HeatWave LITE base layers offer supreme versatility for staying active in a wide variety of temps and conditions. 

Seirus HeatWave™ technology is a dual-stage heating system that combines reflective technology with kinetic properties to amplify your body heat and reflect it back to you. By itself, the uniquely engineered Thermal Reflective Layer amplifies 20 percent more warmth inside than traditional linings. Additionally, a kinetic process uses the wicking energy to generate a 4-5 degree increase in warmth, keeping you drier, and making for an incredibly thin and versatile, actively performing fabric.

“Adding HeatWave technology to a super lightweight, silky fabric creates a super thin, wear-anytime layer perfect for chilly mornings and evenings, or as an additional low volume layer in the coldest months,” said Danica Carey, Director of Marketing at Seirus. “We’re all about solving problems, and with the range of temperatures one can experience through the course of a day, we are making sure there’s an option for everyone. The HeatWave LITE Base Layer performs across multiple activities and applications.” 

Reversible for more than twice the versatility, HeatWave™ LITE Base Layers keep you dry, comfortable and at just the right temperature. Lightweight four-way stretch HeatWave fabric provides silky soft comfort and warmth, and breathability and moisture wicking keeps skin dry and healthy. It is available in women’s and men’s tops and bottoms and will be at retailers in November.


HeatWave™ LITE Base Layers

Silky soft and reversible for ultimate utility and lightweight warmth
Men’s and Women’s Crew Neck Reversible Top MSRP $74.99
Men’s and Women’s Reversible Bottoms MSRP $69.99


  • Classic Fit
  • Reversible with reflective hits at chest and legs
  • Lightweight Heatwave™ fabric for all-season warmth and rapid wicking
  • Fabric is breathable 4-way stretch with moisture control
  • Anti-Chafing Flatlock Seam Construction
  • Tops have Raglan sleeves for comfort during intense activities
  • Bottoms have a terry backed elastic waistband for comfort


  • 4-Way Stretch HeatWave™ with integrated spandex for improved stretch & shape retention
  • Moisture Control/Breathable HeatWave™ to stay dry and comfortable

Colors: Carbon



Now 100% Solar Powered California HQ + Warehouse

The first thing to know about Seirus is that we’ve been innovating ways to keep extremities warm and comfortable, resulting in more than 20 patents from 1978-2021 including one of the first to the market with rechargeable heated gloves. From skiing to celebrating, we use the most advanced fabrics and technologies in a unique R&D culture where everyone at our family business critiques, tests and designs products that redefine all-weather comfort for your head, hands and feet. And did we mention we’re a family business? So we take care of our employees, our partners, our suppliers and our customers with the same care we give our products and processes, making sure they’re all durably made and awesomely comfy. 


Alli Noland