Uniqlo Mens HEATTECH Long Johns. Size M.

Mens Size M Grey Highly functional innerwear that is warm and easy to move in. - Sleek fit stays hidden under bottoms. High-performance innerwear with insulating, bio- warming, odor control, anti-static, quick-drying, shape-retaining, moisture-wicking, moisturizing, and deodorizing comfort features. Ultra-stretch fabric that stretches with your body's movements. Made from material that feels soft and comfortable to the touch. Perfectly-fitting innerwear doesn't catch on bottoms.