The initial 0.02 second vector (1) reflects the small Q wave in leads I and II and the small R wave in leads II, III, and aVF. It is directed inferiorly with a frontal plane axis of approximately 100 degrees. The main QRS vector (2) reflects the R waves in leads I, aVR and aVL and the S waves in leads II, III and aVF. It is directed superiorly and to the left with an axis of approximately -70 degrees. This is abnormal left axis deviation. The loop incorporating these individual vectors is inscribed with a counterclockwise rotation and is characteristic of uncomplicated left anterior fascicular block.