@efel If you need 1000's of K210 you should contact Kendryte derectly, otherwise your best option is to buy either Siped's M1 module (Taobao shop) or Widora BitK210 module (Taobao shop). Price is almost the same (6~7 US$), you can buy both via Supebuy Taobao agent if you live outside China. Edit: You can also buy a K210 chips for ~3.83 US$ at Sipeed's Taobao shop..