The table below summarises the plug types, voltage and frequency of electrical current in both Cook Islands and Guinea-Bissau.
| Cook Islands | Guinea-Bissau | |
|---|---|---|
| Plug Types | I | C |
| Voltage | 240V | 220V |
| Frequency of electrical current | 50Hz | 50Hz |
Cook Islands uses Plug Type I.
You will need this adaptor:
Socket Type
(Cook Islands) to Plug Type C
(Guinea-Bissau)
The voltages found in Cook Islands (240V) and Guinea-Bissau (220V) are not exactly the same, but the difference is tolerable, so you should not need a transformer.
The frequency found in Cook Islands and Guinea-Bissau is exactly the same (50Hz). Timing devices and appliances that use motors will function as expected under this frequency.