HEROBIKER Thermal Underwear Boys Ultra Soft Fleece Lined Kids Thermals Long Johns Top Bottom Warm Set for Winter Skiing

I ordered a size small for my son and it fit great. He normally wears a size 6 boys and he is on the slim side. The material is very soft but thin. It’s not what you would normally consider fleece lined. It worked well for what I needed.

Very thin material. Bought for my son to wear under his costume while trick or treating and was way too thin. Did not keep. Him warm enough. Bought because they were supposed to be fleece lined but not thick enough.

My son loves these because of the fleece inside and the silky outside. Keeps him warm and it's easy to layer. I they do seem to run on the small side mostly in length both top and pants. I'd recommend sizing up.

I ordered 2 sets of these for our ski trip to wear under the kids' bibs. My boys wear a 10 husky and 12 regular. I ordered both an XL b/c they don't like clothes too tight. They fit just as expected - not too tight but a close enough fit to go under the ski bib. If they were going to wear them under jeans/regular clothes, I would have ordered a large for both. Both boys weigh between 92-98lbs.

Purchased size medium to keep my 7yo son warm during early morning soccer games. He prefers to wear the thermal underwear rather than a pair of athletic pants for games and practices. They fit perfectly and very soft, but should have sized up to get at least two years of wear.