You can tell whether it is a Magic Pie or a Smart Pie by its size:
The Magic Pie
(top photo) is much bigger than the Smart Pie
(lower photo).
The middle photo shows the Magic Pie Edge, which is sized between the Magic Pie and Smart Pie. All three motors shown above are installed in the same size 26" rim, but the Magic Pie Edge shown is a front motor.
Unfortunately, you can't tell by looking whether they are versions 3, 4, or 5.
If you programmed yours with a 10 pin cable it will be version 3
(much noisier under load with non-vector controller).
Version 4
(MP4 and SP4) are much quieter because of their vector controllers.
Please note that the Bluetooth dongle is only compatible with version 5 of the vector controllers
(MP5, SP5 and MP Edge).
The Bluetooth dongle, USB programming cable and the BAC-601 display units
all connect to the same
5 pin connector coming from the controller harness
(but only one at a time )Alan