There are six different types of electrical plugs used around the world, but one of the most common ones uses three cylindrical prongs. It is not the type of plug that you are probably used to, with two flat prongs and one round one, which is only used in a few places outside of North, Central and South America. In Bulgaria , a country that borders the Black Sea, the plug used is the the cylindrical-pronged one. It is also used throughout the rest of Asia and also Europe. This is why you won’t be able to plug any of your electrical appliances in if you go to Bulgaria .
If you discover that you need a voltage converter for some of your items, look for one that lists a 25% higher wattage than the appliance you plan to use it with. The wattage of your appliances may be indicated on the device itself, but if not, you can multiply the voltage by the amp, and the number you get will be the wattage.