Hawaii uses the same electrical standard as the rest of the United States: 120V at 60Hz, with Type A/B plugs (two flat parallel pins, sometimes with a third round grounding pin). Visitors from countries using 220-240V systems (Europe, Australia, most of Asia) need a plug adapter and, for sensitive electronics not rated for dual voltage, a step-down voltage converter. Most modern phone, laptop, and camera chargers already accept 100-240V, so only an adapter is typically needed.