Castelli has created a bib short that could be worn under a lighter pair of tights in Spring or Fall or potentially a very cool Summer morning. They are exceptionally comfortable and I have worn them on fifty mile rides with little complaint form my backside. My pair of size medium fit my 5 foot 9 inch frame nicely. I usually weigh between 160-165 pounds. If you are tolerant of "lower" temperatures these would be excellent for 50-60 degree rides all by themselves. With all my new Castelli gear I have stopped putting them in the dryer after washing even on the super delicate setting. Read the directions for yourself and given the amount of money involved I say err on the side of caution. I wish I could put them in the dryer but I'll trade off the time between uses to have them last longer. I like them that much.
Great for cooler weather! I was looking for a midweight bib to get through the winter and this definitely was a good choice. Fit and overall construction are what I expect from Castelli and these are my go to shorts when the temperature drops.