Castelli Mezza Wool 9 Socks
Made for chilly days with slightly thicker fabric than their summer socks. This one is made for those in-between conditions: nearly as thin as a summer sock so it fits into your shoe easily, yet in Castelli's luxurious merino wool for warmth.
Great half, far superior to other brands in the market, great quality elasticity. Anyway, it's a Castelli product.