This is a standard type self-help tool with a wooden, arc-shaped design, suitable for training and rehabilitation. - Type: Wooden - Shape: Arc - Standard Type: Solid wood standard type Thank you for looking. I purchased this to help my parent with their lack of exercise, but they haven't used it at all, so I'm putting it up for sale. This is a custom-made product, so it was quite expensive. I hope someone who needs it will use it. Thank you.