Kaidomain SST90 driver s010139 any info?

Got this in the mail today, no testing yet.


Any threads about it I may have missed? It is huge, but looks like they could have made the board a lot smaller. Funny there are 3 concentric rings at the bottom instead of your usual positive center and negative outer. I am wondering if somehow bridging the two rings allows you to select modes like the drivers with stars. But, the entire middle ring is connected to itself, not like you would have 4 or 5 different connections to bridge so probably thats not the case.

Also, I haven't gotten my SST90 in the mail so that puts a damper on things.