LiFePO4 24V 3A Chargers received from Hong Kong

These are tpics taken few weeks ago when I received the first 3 low cost LiFePO4 chargers from Hong Kong. They will allow a slow charge at 100W each, but multiplied by the number of chargers (6 in total soon, as I ordered another set of 3) it will charge at around 600W and I can switch them ON & OFF one by one, adjusting the use of "green" power going into my batteries

AC 110-220V, they give 30V at 3A DC and have a tiny fan (I did not see until I got them)