Kuryakyn ISO Throttle Boss With the addition of a throttle boss can make the difference between a quick trip or a cross country adventure. Features great style with a larger surface area and pad, to provide even more comfort to easing tired hands and forearms. They are easy to install and can be adjusted to suit your needs. Features: Updated styling with a larger surface area and pad Provides even more comfort than the original design Eases hand and forearm fatigue Simply position the throttle boss under the palm of throttle hand, which allows driver to slightly relax grip on the gas, while maintaining a constant speed Fits left or right side Grips are not included Fits all Kuryakyn ISO grips