Heat Holders men's thermal underwear is designed to keep you exceptionally warm, whether you're indoors or outdoors. Crafted from 100% Polyester, these thermal long johns feature an elasticated waistband for a comfortable fit. The advanced thermal microfleece, enhanced by an expert brushing process, creates a soft, fur-like pile that traps more warm air close to the skin, maximizing thermal performance and comfort for extended warmth. These base layers are ideal for layering, providing a smooth, slim-fitting profile under clothing. They also incorporate moisture and odour management technology to help you stay warm, dry, and fresh throughout the day. Heat Holders offers different thicknesses for varying conditions: Original (thickest, for extreme cold), Lite (medium, for very cold days), and Ultra Lite (lightest, for everyday cold). Choose the thickness based on your activity level and the ambient temperature. Machine washable at 30°C; tumble drying is possible but line drying is recommended for best care.