The Kuryakyn 6319 ISO Throttle Boss can make all the difference in the world on a long ride. The Throttle Boss is a small, adjustable paddle that is positioned under the palm of the throttle hand allowing the driver to slightly relax their grip on the gas and still maintain a constant speed. Designed in gloss black for a uniform look to your ride and includes (1) ISO Throttle Boss and (4) #4-40 x 9/16" socket head cap screw (SHCS); suggested tools for installation (not included): set of hex wrenches. The Kuryakyn 6319 ISO Throttle Boss is compatible with all Kuryakyn ISO-Grips, ISO-Flame Grips, Transformer Grips-Left or Right Grip.