WHAT IS THE DIFFERENCE BETWEEN THE SOFT PAD AND THE HARD PAD AND WHEN IS EACH RECOMMENDED?

The soft pad is used in all front brake applications as well as the rear brakes in a vehicle going under 155 MPH in the quarter mile. The hard pads have a more aggressive metallic compound and are only used on rear brakes. These would be suggested for a vehicle going over 155 MPH in the quarter mile.