Yes you can use and connect the Keiser M3i to Zwift using the Keiser Conversion Kit. If your M3i is comes with Keiser M Computer, you can use it with Zwift, Peloton and many other applications without the Keiser Conversion Kit. But if your Keiser M3i bike comes with an old Keiser Computer, you will need the M-series converter in order to use Zwift.