I have ordered an almost similar device from ebay (ships from China so I expect it delivered after 2-4 weeks) called AUTOOL BT-360 which is a direct clone of another device (forget the name).I think its quite funny that the same product price ranges from 25 to 50 euros.They probably are not high end devices ,mostly useful toys.
We'll see what happens when it arrives,I have 3 flooded batteries to test used previously , currently and the last is not used yet (all properly maintained) in my Ford Fiesta.
-one 12 year Ford original (Silver Calcium) old worn (but not dead) battery 43Ah 390CCA,worked for 6 years then replaced with the:
-one working but old (6+ year old) currently in the vehicle , Banner Uni-bull 5100 47AH 390CCA
-one made in Greece (no brand name) 3 years old but never used (only charged periodically) supposed to be 50Ah and unknown CCA
It would be interesting , if there are quite a difference between the results ,this little thing should work as expected
I also have an AGM 4,5 year old and well maintanied battery in my Honda , and a LiFePO4 in my Kawasaki
Should be interesting to see the result on those too.