Set of 10 Nesting Rings in 6mm MDF 
The largest ring is approx 22cm across 
Each ring is 1cm wide 
 
They come as you see them in the photo, but you are welcome to ask for a hole in each one, (In the notes section) if you wanted to make a mobile or something similar from them
Add a 3mm solid base for just £2 to make it into a concentric puzzle