Medela's Lactina Select works, with a regular outlet adapter in countries
with 220 service.  The Lactina Plus can also be used with the battery pack.
 First you recharge the battery using an outlet adapter.  Then you pump using
the battery.

I have had several mothers travel both to Europe and Asia using the Lactina
Plus without problems.

I have had mothers tell me they had problems getting through customs in
Narita (Tokyo), Agra (India) and in Taiwan.  I now suggest moms also take
Medela's Breastfeeding Information Guide with them because it has a
photograph on the Lactina in use.  One mother reported having to demonstrate
the pump in front of five gentlemen from customs.  Not fun.

Elizabeth