My son works outside in single digit temperatures and dressing him warmly but so he can still move around is a challenge. Duofold long underwear provides a soft and warm base layer that really does keep him warm with its double layer construction. Make sure that all of the bottoms have the y-fronts as not all duofold styles do and no guy wants to be undressing in the cold to use the restroom. These also stand up to numerous washes and dries and get softer and nicer with wear. A good quality product that performs the way it should and is worth the money as these are holding up through their second winter season to date. The colors are nice too and include blue and black as well as the traditional white. Recommended.