This is a set of 6. These are masu (wooden square cups) used for a kagami-biraki (ceremonial sake breaking) ceremony at a certain lodging facility on New Year's Day 10 years ago. They were washed in a dishwasher and stored in a dark place, so there is not much deterioration due to aging. I think they can be used for measuring, or for taking photos with a mound of rice, etc.