Instruct: Classify a review into positive or negative sentiment.
Query: Not midweight

These are not what you want in cold weather. they are not mid weight, they are light weight. You can watch TV through a single layer. Much thinner than a quality T shirt. They fit well and look good but I wore them under my uniform on a 45 degree day and could not tell that they helped at all. I bought several of the tops and bottoms but they are of little use.