if you have a laptop or other charger if you look up "figure 8 plug" thats the tail that goes from the wall to your power brick. ive got one for uk/commonwealth countries, the euro style prong and the us/jp style. makes things easy and I've not tripped any breakers like i have with wall adapters adapters. most power supply can do 110v and 240v and will invert/convert the volts. they also turn ac into dc. tldr "figure 8" plugs are the part that plugs into a power supply from the wall and is real convenient for electronics like laptops and chargers.