It's a support for DWARF II, you can fix it on gutter.
You need screw (1/4" 18 mm) like this to fix DWARF II on support : https://www.amazon.com.be/gp/product/B084M4563L/ref=ppx_yo_dt_b_asin_title_o04_s00
The author marked this model as their own original creation.