Like all Carhartt thermal underwear, we've designed this new midweight cotton crew neck top for comfort, warmth and durability. Made of premium, 9.5-ounce, 100% cotton, it features rib-knit neck and sleeve openings that keep warm air locked in. The fabric, which is 30% heavier than most other cotton thermals, also traps body heat in for warmth. All seams are flat-locked for added durability, comfort and strength, and its low shrinkage provides a consistent fit. For function, ruggedness and ease of movement, this job-tested crew neck has it all.For over 115 years, Carhartt has manufactured premium workwear known for exceptional durability, comfort, quality of construction, and fit that you can feel in the fabrics and see in the performance.