How do I change the incline of the treadmill?

There are three incline levels available. Before changing the incline, remove the key, unplug the power cord, and fold the treadmill to the storage position. Remove the incline pin from one of the incline legs, adjust it to the desired position, and fully reinsert the incline pin, then repeat for the other incline leg. Before using the treadmill, make sure that both incline legs are at the same height and that both incline pins are fully inserted.