The voltage in Spain is 240 V at 50 Hz. Most of our electronics, Apple chargers, laptop chargers are dual voltage so that’s not a problem. We will need an adaptor plug to fit into their sockets. We should use either the type C or the type F adaptor plug. The type F adaptor plug is slightly larger for grounding. This is something you might want to bring if you have an hairdryer or curling iron . The hairdryer would probably need a voltage converter also as well as the adapter.