The short-cut rows allow the long bristles to work deeper into the hair. This creates more lift and volume to the hair, prevents the matted look and invigorates gentle stimulation to the hair base for new hair growth and faster hair training. The short rows are cut to a length 1/4” shorter. The soft, gentle grade of synthetic bristles prevents the brush from being too harsh as compared to stiffer roto brushes that can scratch and irritate the hide. Lock nut keeps the brush securely tight and free from spinning loose. Flat side of bolt allows it to lock tight in the drill and keep from spinning loose.