The Box Two shifter is the only shifter on the market (other than our Box One) that comes factory stock with a hinged clamp. Box Two is our performance tier so this shifter still maintains the durable cast aluminum top shell but trades out the Box One's 1-piece pull-lever for a 2-piece resin and steel variant. All Prime 9 shifters take advantage of the 9-speed's inherent durability, simplicity, and reliability. Not only is the shifter mechanism joyfully simplified, but fewer shifts are needed for every mile of travel. And the best part is? Prime 9 is also terribly forgiving so you won't have to constantly adjust your set-up.