One of the warmest thermal tops you can buy. There are few on the market with such insulation. However, be careful, it's not for every day of winter, especially in Greece, when the temperature is above 4-5 degrees it becomes unbearable and definitely not intended for sports activities.
When it comes to cold, we're talking about an incredible product, I wore it in Austria at -3 degrees with just a jacket on top and most of the day I had to take off the jacket.

By far the best thing I have worn.
I live in Norway and work outside in -20 degrees.
I wear the thermal underwear, a thin fleece shirt, and the jacket which is a nylon from the series.
I don't feel anything, it's awesome.

Finally, I found a truly warm garment. It is quite thick as it has fleece on the inside and you feel like you are wrapped in a blanket. It is worth 100%. I wear it at -20°C in Florina, that says it all.