Shift knob designed for smooth and seamless gear changes; Steel construction for added weight and easier shifts 12.8 oz/360 gram total weight for precise and accurate shift feel; Ergonomic shape allows for smooth shifting and comfortable hand position Purchase includes three insert sizes to fit various applications Insert thread pitch sizes: M8 x 1.25, M10 x 1.5, M12 x 1.25 Mishimoto Lifetime Warranty