19mm wooden cube blocks. I bought them on Amazon a few years ago. There are 90 blocks in total: 15 blocks x 6 colors. I used them to help my child practice counting in math. I haven't used them many times, so they aren't heavily soiled, but there was a crack (or similar) from when I originally bought them. Please understand that these are used items before purchasing. They can be used for number and shape problems. The different colors are also convenient for calculation problems. They were stored in a 100-yen store plastic case.