I've used these a few times for diving, but they were too small for me, so I'm selling them. I think they're around 27-27.5cm. They have felt soles, so they're non-slip and stable on rocky shores and reefs. They can be used for diving, snorkeling, other marine sports, and in the sea or rivers. They are used, but in good condition. I'll sell them cheap to someone looking for felt sole boots. Also selling cheap fins.