Donburi Bowls, Set of 2, Noodle Bowls, Soup Bowls

I am currently decluttering my parents' home ??

This was stored in a cupboard.

Diameter: approx. 15 cm
Height: approx. 7.7 cm
Please excuse any slight errors as these are amateur measurements.

As there is no box or booklet, I do not know the details, including the material.

Would this be suitable for someone looking for a bowl for donburi, hot udon, or hot soba?

The tatami tray shown in the photo is not included in this listing.
Please make your decision based on the photos and description. Thank you for your understanding.