Free cup soba choko 5-piece set

A set of 5 soba cups in a refreshing blue tone.
Can be used in various ways as free cups.
I have forgotten what type of pottery they are.
Some have been used once, and some are unused.
They have been stored in a cupboard.
I don't think there are any particular issues, but please forgive any oversights.
The approximate size is 8.5 cm in diameter and 6.5 cm in height.
Thank you to those who understand the above.
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