This is Under Armour's UA HOVR Infinite 4. I'm selling them because I don't use them much anymore. The size is 27.0cm. I wore them often, so there's a feeling of use and some dirt, which is why I'm selling them at a reduced price. Perhaps because I washed them twice, the chip inside that connects to a mobile app to track running distance, etc., seems to have stopped working. They are still usable, but please purchase only if you understand that they are used items.