My husband works outside and we usually buy the thermal underwear at a big box store. We didn't know about Under Armour's Cold Gear Base Layers. Wow! What a difference! Yes Under Armour base layers are very expensive but completely worth the cost! He's warm and comfortable with freezing temps without layering. He's able to do his job without the bulkiness of his work gear bibs for winter. He loves them so much that he tends to wear them around the house! We have bought the 3.0 base layer shirt and top for different temps when it's warmer. For reference, we specifically got these since they were "fitted" not compression leggings and he's 5'8" and 185 lbs and he fits perfectly in the XL.