S.E. Asia electrical plugs?

We are doing the Vantage Irrawaddy & Mekong combo trip in a few weeks and wondering what electrical Adaptor Plugs we might need. I am aware of voltage and frequency differences, but am not using electricity in heating elements (eg hairdryer) but rather using it to power or recharge electronics which have built in voltage transformers. We will be on the chartered RV Irrawaddy Explorer and the RV Mekong Navigator plus staying in western chain hotels (Sheraton, Sofitel, InterContinental). There are internet reports of multitude types of electrical sockets, but it seems that US flat prongs and/or European round prongs will work the majority of the time. I'm looking for comments pro and con on carrying any other adaptors. TIA

Thom

Thom,

That was was the only type of adapter we took on the Irrawddy (did not do either extension). We did need and use a small multi-receptacle strip especially on the boat for camera batteries, Ipads, phone.

In Cambodia and Vietnam, all the chain hotels we stayed in seemed to use the same type of universal power socket which took USA/UK/EU/Australian plugs without problems.

EU and USA type plugs were all we used, including on the Pandaw owned ship.