Customized version of https://www.thingiverse.com/thing:3169279

Created with Customizer! https://www.thingiverse.com/apps/customizer/run?thing_id=3169279

Using the following options:

seed = 89
base = rectangle
base_height = 1
num_sides = 9
side_length = 20
position = circumscribed
separation = 1
supports = no
size_x = 40
size_y = 40
diameter = 40