What is the charging speed with the Tesla adapter?
It's just an adapter--it does not change anything from the charger, so the charging speed will be the same as the charger used and whatever the vehicle can draw.
I own two Tesla wall chargers and at these two houses I have a Tesla Tap Type DSS-EV-40P-V3 (40 amp Tesla to J-1772 adapter).
I also own a new Tesla Model 3 so I now also use 240 VAC to charge my Zero's with, using the above adapters.
At my third house, where I mainly only want to charge my Zero DS 6.5,
I use one of these. Which also can be used to charge my Tesla.
At each house I also have two Zero quick chargers--all running from 240 VAC.
This way I do not have to run any extension cords to run the three Zero chargers. All of my Chargers are on 60 amp 240 VAC circuits, but the MustStart charger is on a 50 amp outlet.
-Don- Auburn, CA