Dave Plowman (News) wrote on 02/01/2019 :
All you need to prevent wrong connection is an internal relay with the
coil fed via a diode from the battery. That's been a feature of many for a
long time.

I am aware of that thank you, but this charger doesn't not suggest it
has any reverse protection. It appears to have just an on/off mains
switch and an ammeter. Nothing to indicate the charge is complete, so
likely just a transformer and a rectum fryer inside.