I have a couple of those as well from ALDI, I take them with me when I go camping with other site members we stop in camp sites with hookups, re the functions mine has motorbike, car and car again although for cold weather? Unsure why that function is there, the charge rate is the same?
Either way, I take the two as they are small and compact, and of course if one fails I have a spare, I must have a fridge.
Regards
Dave