To replace the battery of the ONcoach 100, turn the battery cover to the left and remove it.
Gently pull the black tab to extract the battery.
Insert the new battery, while making sure that the positive pole is towards the bottom of the battery cover.
Close the battery cover by placing the 2 triangular indicators face to face and making sure to reposition the tab on the battery.
Push the cover until it closes properly.
Turn it to the right until the triangular indicator is vertical.
Synchronize your ONcoach 100 with the application to reset the correct time.