Thank you Roberts!
I was thinking in a 40liters pack. Considering that I'll carry of 5 t-shirts, 2 pants, a pair of shoes, a sweatshirt and not more. I don't know about size and weight but I was thinking to UL pack looking forward for my mountain trekking. But I'm worry about the resistance of the materials that I don't know anything about this matter.
I don't know if I answered correctly to your questions. If not please tell me wink
Nicola