It's a tiny, self watering planter with water level indicator.
Water reservoir is in the bottom. A small string transfers the water to the soil.
Needed parts:
Water indicator is obtainable via web, or in typical german hardware stores (toom, obi) and costs about 2 €.
It probably would not be too hard to design one by your own.
Print instructions:
Inlay.STL | 5.0MB | |
Planter.STL | 6.2MB |