A Teams model is certified for Teams, i.e. it supports Plug & Play with Teams, the default softphone communication is automatically selected for Teams, and there are Teams answer and hang-up functions. UC versions are also usable with Teams, but their automatic features are then designed for Avaya or Cisco calls. Additionally, there is confusion as both versions are offered with a USB-C dongle or with a USB-A dongle for communication to the headset. It's a bit of a mess with this UC and teams certification.