Filter paper holder for the top of the wdt tool. For size 58mm. In two pieces, so you don't need a support.
WTD tool: https://makerworld.com/en/models/112678#profileId-371033
Tamping station: https://makerworld.com/en/models/390100#profileId-291055
Middle stand: https://makerworld.com/en/models/467810#profileId-376912