A quick throttle uses a larger cam, or 'pulley', to open the throttle faster than the stock unit does. Less overall rotation is required to reach full throttle and this can be benefit to riders with limited wrist mobility and it also allows you to maintain a proper riding position with less elbow drop as you crank the throttle.
This is an excellent quick throttle. The Made in the USA, the G2 unit uses self-lubricating Delrin bushings in a tube machined from 6061 aluminum which provides an ultra-smooth feel. The end of the tube is removable allowing for bar end plugs or hand guards to be installed.