No discounts. Will be shipped in an envelope. This long-sleeve shirt incorporates innovative technology that generates heat when you move your body in the cold. It uses a material that warms up and generates heat as the fabric repeatedly stretches, thanks to special functional yarn and fabric design. The heating effect occurs not only when the fabric is dry but also when it gets wet, through the same stretching motion. This means you can still benefit from the heating effect even if your clothing gets wet from sweat or rain, making it invaluable for winter sports. Furthermore, the heating effect weakens when the surrounding temperature reaches 25 degrees Celsius, preventing the inside of the garment from becoming too hot. It also features sweat-wicking and quick-drying properties to reduce chill from sweat. The highly stretchy material and unique three-dimensional design allow it to flexibly follow dynamic body movements. It also has UV protection (UPF50+, 95% or higher UV cut rate *data at 30% stretch) to protect against strong sunlight. The high-neck design keeps your neck warm and is useful for winter golf, baseball, winter sports, trekking, and more.