Like twisty said...get them from gixxer.com. you will NOT find a better price on them. they are made by a guy named jeff wallace and sold by gixxer. he even offers one with a toggle switch. also it makes the coomputer think its in 5th gear all the time. the timing retard doesnt kick in till the upper rpm range of 6th. i also hear it smoothes things out on the bottom end too like that jerking trait that busas have when cruising at low speeds.