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FORTRESS BasePro 300 Base Layer Thermal Pants, Men's Moisture Wicking Cold Weather Base Layer Underwear, Performance Insulated Long Johns, Black
The FORTRESS BasePro 300 Base Layer Pant is a high-performance thermal underlayer designed for cold-weather protection and moisture management. Built to be worn next to the skin, it helps retain body heat while keeping you dry and comfortable during active use in extreme conditions.
Constructed with advanced moisture-wicking fabric, it pulls sweat away from the body to help regulate temperature and reduce chill. The lightweight, flexible design allows for easy movement, making it ideal for layering under midlayers or outer shells in harsh winter environments.
Engineered for durability and everyday performance, the BasePro 300 series is designed for cold-weather work, outdoor labor, and extended exposure to low temperatures where reliable insulation is essential.
XS: Waist 28" - 30"
S: Waist 30" - 32"
M: Waist 32" - 34"
L: Waist 36" - 38"
XL: Waist 40" - 42"
2XL: Waist 44" - 46"
3XL: Waist 46" - 48"
- Item Features
- Attributes
- Next-to-skin base layer design - engineered to be worn directly against the skin for maximum warmth and comfort in cold conditions
- Moisture-wicking performance fabric - pulls sweat away from the body to help keep you dry during activity
- Thermal insulation technology - helps retain body heat in cold weather, even during movement or wet conditions
- 4-way stretch construction - provides full mobility and flexibility for work, outdoor activities, or layering
- Lightweight and low bulk - designed to reduce layering while still delivering strong cold-weather protection
- Breathable performance material - helps regulate temperature and reduce overheating during exertion
- Fast-drying fabric blend - dries quickly after sweat or moisture exposure for sustained comfort
- Comfort waistband design - soft stretch fit for all-day wear without irritation
- Durable polyester/spandex blend - built for rugged use while maintaining flexibility and comfort
- Cold-weather performance range - designed for use in sub-freezing to cool conditions when properly layered