I usually have size 39/40 - socks in Gr. 35-38 fit me perfectly, while the socks in Gr. 39-41 unfortunately they are too big. The smaller sitting in sport (I use them for "Fit-in-the-pregnancy-course) super and do not slip. Delivery was problemos and quickly. The excessive socks in Gr. 39-41 I have not returned, but for the reserve "household".