The chargers are supplied with a selection of power outlet adaptors for use in multiple countries. Before first use, select the appropriate adaptor for your country and attach it by aligning the male notches on the back of the adapter with the female notches on the power block then twist clockwise, the adapter will click and lock into place. To switch adapter, push and hold down on the locking tap, located on the power block, and twist counterclockwise to release/open.