These fins fit very well on short legs, for small people. So, even if you are a small person about 140 cm (4 feet 7 inches) tall and/or with short legs, the fins will still fit you.
I normally say the one fin size fits everyone over about 140 cm (4 feet 7 inches). But actually, they will still fit you even if you are a bit shorter than that. Having shorter legs doesn’t really affect how the fins fit on your legs. Whatever your leg length, the straps still go around your leg just above your ankle. The straps are also highly adjustable to fit you properly.
See all FAQ about the adjustable fit of leg fins.