What is the difference between the Chat 50, 60, and 70 (or 150, 160, and 170)?
The Chat 50/60/150/160 are general purpose speakerphones. The Chat 70/170 has special firmware to allow you to pick up and end calls in Skype For Business from the device using the Call Control button on the unit. The 70/170 still works as a general purpose speakerphone as well.