For slightly tapered baskets.
2.01 in (51.05mm) OD and tapers up to 2.025 (51.43mm) OD
It was designed for this bottomless portafilter:
https://www.amazon.com/gp/product/B08N56L6PP/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
Print with PETG to be food safe.
.Step and Fusion360 file included it you need to modify.
The author hasn't provided the model origin yet.