The article does not mention if these are retail drives purchased from an authorized source or shucked USB externals: https://blocksandfiles.com/2020/04/14/wd-red-nas-drives-shingled-magnetic-recording/?fbclid=IwAR3hwSLG89Bt7v5OWeAYw7T6ZjDHb_noDP1J-qsrLyu9BZrSjmyz1EizyQs