Air Busan's official dangerous-goods guide lists a limit of two external power banks rated at 100 Wh or less. Batteries rated 101–160 Wh require airline approval and are limited to two in total in that higher-capacity category; above 160 Wh they cannot be transported. Carry power banks with you rather than in checked baggage, and protect their contacts against short circuits using individual bags, caps or insulating tape. They must not be stored in overhead bins, and in-flight use or charging of power banks—including charging another device from them—is prohibited. A power bank without a verifiable Wh marking or one recalled for fire risk may be refused. Batteries installed in electronic devices have a different row of the airline's policy.