I purchased these with the intention of resuming horseback riding, but I am now unable to due to a move, so I am putting them up for sale. The size is M, but they fit me, and my calf circumference is 35cm. I think they can stretch to about 36cm. According to the previous seller, they were used about once a month for about a year and a half. I haven't used them since I bought them, but there are some noticeable scratches and stains. Please feel free to comment if you have any questions.