Review on USA-Made Boys Thermal Underwear Set - Long John, Soft & Breathable Cotton Base Layer by City Threads by Alfonso Tipton

Bought 3T as a size reference for my almost 5 year old - he is 4 but will be 5 in a month and is less than 4. I don't know him specific sizes but in general, he usually wears a 4T/4 top (not tight) and 3T/36m. floors. The 3T set fit our son perfectly - definitely not even a tad loose like the three model boys on the product description picture but a lot tighter which is what we wanted as a base layer. The sleeves are a bit short for our boy as he normally wears a size 4 top, but the waistband and length of the pants were perfect. They were fantastic for cold weather vacations as a base layer. I was worried they would be too bulky/too itchy to wear under other clothes but they are not bulky at all - actually quite thin but surprisingly very warm! It's kind of a very tight weave so it holds in heat rather than having tiny sewing holes all over it like "waffle weave" I imagined. And super soft and comfortable at the same time! I really liked that they were thin enough to take up very little packing space when we were trying to travel light. We ordered 2 sets of these (both in 3T). My son wore one or the other every day during our 9 day vacation in 30-45 F weather. I'm glad they worked.