The new Amazfit Band 5 from Huami is now available to purchase either from Amazon or Amazfit's US online store. The smart band, which costs US$49.99, provides blood oxygen measurement, Amazon Alexa, the PAI health assessment system, and up to 15 days of battery life with typical usage or 25 days in power-saving mode.
https://www.notebookcheck.net/Amazfit-Band-5-with-blood-oxygen-measurement-and-Alexa-virtual-assistant-is-now-available-to-buy-from-Amazon-and-Amazfit-US-for-US-49-99.495773.0.html