I did this has a charging jack only found out later.
The charger offered here differs slightly from the image.
It is considerably narrower and has a warning light which, however, only indicates whether the charger is on (no charge indicator)
Fits perfectly into the charging socket of the Sigma LIGHTster (was indeed to be expected so)
Ideal in combination with Eneloop batteries.
Charging time is said to be 6-8 hours.
I'm very satisfied with the purchase.
The price of 7.45 is also fine.