Castelli's Rosso Corsa sock has a mesh top and bottom to guarantee maximum ventilation. Second, the sock material is antibacterial Meryl® which is smooth enough to slide against your shoe, but not against your foot, thereby reducing hot spots and blisters. Finally Castelli has a compression cuff and mid-foot support band so all that technology fits snug (but not too tight) against your grateful foot.
Ive had many long rides with no hot spots thanks to these socks. Your feet will thank you.