PING Scottdale Tec Ketsch Onset BlackThe alignment aid features a long line and a single dot. Its a result of eye tracking research that shows that combining a line and a focal point calms the vision right before the start of the putting stroke. A third model (Hayden) uses a face balanced heel shafted orientation to promote a cleaner view of the alignment aid and a straight back, straight through stroke. The lightweight aluminum construction saves mass thats redistributed in a steel sole