OK, to clear up any confusion:
As I understand it, if you buy an SL-C1000 from Japan, or from PriceJapan, you will get a tiny PSU which is the EA-72 (100V, 50/60Hz, 11VA input, 5.0V, 1.0A output). This has plugs suitable for the Japanese market, apparently, and is rated at 100V. I don't know if it's suitable for use in the USA, but the previous owner of my 1000 did use it in the USA with an adaptor.
If you buy an SL-C1000 from any reseller such as Conics, Dynamism, Figlabs, Pulster, ShirtPocket, Streamline, Trisoft or anyone else who knows what they're doing and understands their obligations, you will get a worldwide PSU suitable for use anywhere in the word when used with appropriate converter plugs. Figlabs provide the Sony PSP charger and have taken the 1000/PSP charger through CE mark certification, most others to the best of my knowledge provides a Sharp EA-70 - Trisoft have taken the EA-70/SL-Cxx00 through CE mark certification.
The EA-70s is a lump which needs a "figure of 8" lead from the plug socket to the PSU. The rating is 100-240v input, 50/60Hz, with 5.0V DC 2.0A output.
The EA-75 is the charger that comes with the 3100. This is a charger with japanese-style plug moulded into it, so for use in other markets I think you need a plug adaptor. Interestingly, it is only rated for 1.0A output rather than 2.0A.
Sorry to give such a long answer to a simple question, but I'm trying to get to the bottom of what is supplied in the box with every model. I hope it helps somewhat.
