- Specially knitted to trap air for a soft and warm feel. <br>- 2.25 times* warmer than our regular 'HEATTECH'. *Based on CLO values, which measure clothing's thermal resistance. Comparison with standard 'HEATTECH'. <br>- High-performance fabric with Heat Absorption, HEAT RETENTION, and moisture-wicking comfort features. <br>- Ultra Stretch fabric. <br>- Soft texture and excellent shape retention. <br>- Brushed for warmth. <br>- Body width and sleeve length designed to wear like a long-sleeved T-shirt or sweatshirt. <br>- T-shirt style collar is easy to layer.