Our billet shifter knobs are designed to fit the curvature of the hand. As you pull down two fingers go underneath the curve and two on top, then when you push it fits the palm of the hand. We added the custom smooth knurling for grip it doesn’t matter if you are barehanded or wearing gloves. They come with 1/2-13 threads to fit the Winters, Side Winder shifter, or anything that has 1/2-13 threads. The threads are cut deep inside to keep the weight low and close to the shifter.