Who's "they" you might ask? Specifically Nate at First Lite. This piece is really comfortable and warm. When he and I talked, he said I would be able to feel the difference when I took it out of the package, and he was right. By far the nicest base layer piece I've owned for colder weather hunting. The thumb holes work perfect, and the length in the sleeves is great for wearing under other pieces. Sometimes with those thumb holes on other brands they feel like they "pull" in the sleeves when you use them, but not with this piece. As a guy who is pretty thin overall, the piece is definitely not compression fit, but works great at keeping me warm so far on the cold weather hunts here in Wisconsin. Extremely happy to have taken Nate's advice and purchased this with my other First Lite items.

Great warmth as a mid layer during late season or an outer layer earlier in the season. Plenty warm but breathable enough for the walk to the stand. This was part of my first First Lite order and it won’t be my last.

Worn with a Kiln and a Guide Jacket, this is my go-to set up in high 30s low 40s. Works great and I would recommend.

XL fits great and is very warm. Makes a great middle insulation layer when bowhunting whitetails in December. This is my first piece of clothing from First Lite.

I am a big fan of the furnace base layers. I hunt in the blue ridge mountains and the weather can get awfully cold. The furnace layers can be worn individually or on top of a thinner layer for maximum warmth. These garments are well made and a must for any whitetail hunter.