Household power supply specifications vary by region. the voltage value is usually between 100V and 240V, while the most common frequency values are 50Hz and 60Hz. the data of overseas territories of some countries are quite different from that of their home countries, so they are listed separately rather than put together with their home countries. in addition, in special areas such as large factories or overseas military bases, there are often situations where the voltage or frequency and value are different from those in nearby areas.