Plug Type in Cuba

In short Cuba uses Type A, B, C and L sockets, running at 110/220 V and 60 Hz. Cuba runs both 110 V and 220 V, often in the same building, and the sockets do not distinguish between them — older rooms tend to be 110 V and newer hotel wiring 220 V. Ask before plugging anything in that is not dual-voltage, because a Type A socket tells you nothing about what is behind it. And here is the part that costs people money: sockets in Cuba accept flat American pins at 110/220 V. A US appliance plugs in with no adapter at all, and unless its label reads 100–240 V it is destroyed the moment you switch on. The fit is the danger, because it removes the moment where you would have stopped to check. The distinction to hold on to is that a plug adapter and a voltage converter are different objects: the adapter changes the shape so the plug enters the socket and passes the local mains straight through, while the converter changes the voltage. Almost everything sold as a travel adapter is only the first, which is exactly why it cannot protect anything. Frequency — 60 Hz here — matters much less than people expect, because any device with a switch-mode power supply converts the incoming mains to DC immediately and ignores it. It affects mains-synchronous motors and old mechanical clocks, which run proportionally fast or slow, and very little else.