Differences between 4Sevens single bay charger V1 and V2
4Sevens is producing a LiIon charger, but the first run had a production fault that could disable the control microprocessor in the charger, due to this reason the charger was recalled and a new version released (V2).
The recall did not required people to return the V1 charger, they would just receive a new V2 charger, but without any accessories. I.e. watch out for any sale of used 4Sevens chargers without accessories.
Here I have listed the external differences of the two charger models:
Review of V1 charger
Review of V2 charger
Note: The better "click" might not be a general improvement, but just variations in the switch.