This is the only type of thermal my hubby likes to wear. One of the reviewers called them 'panty-hose' tops.  That's not accurate because panty-hose are tight and squeeze the life out of you.  The thermasilk crew neck top is thin and sheer with a soft fit, but it's made to be worn as a thermal layer under another top.  It's not meant to be warn alone, except maybe to bed.

My guy wears these skiing under his regular shirt, or even just for daily wear on really cold days.  He wears the silk pants under his ski pants.  They wick the moisture and hold the warm layer of air next to his skin without feeling like anything binding or bulky.  Vibrationally silk is superior to nylon, and weight- and bulk-wise it's superior to cotton.

If you want a natural fiber, light-weight, soft as silk, thermal layer that stands up to the cold without overheating, then I recommend you try the thermasilk.  It's sheer, but it's no panty-hose... it's a superior foundation layer.