They're from PB Swiss, called "BitBlock" haha. https://www.amazon.com/PB-Swiss-Tools-BitBlock-PrecisionBits/dp/B00KRSLE0U?dplnkId=998ae682-def2-4c94-82e6-2acdcdbbe473

Edit: I just checked the price, it's too expensive from amazon.com @16 USD, it's only around 400 Yen or 3 USD in amazon.co.jp (Japan)