Thank you for viewing! This is a set. The red ones are 13.5cm, and the blue ones are 14.5cm. I'm selling these because my child has grown and no longer wears them. They have been home-cleaned. These shoes are from about two years ago. I think they were worn for about six months. There isn't much wear on the soles. They show signs of use, but I think they can still be used. How about them as second shoes?