The Box One shifter is the only shifter on the market that comes factory stock with a hinged (and machined) clamp. Its top of the line and comes packed with other features such as a durable cast aluminum pull lever and top shell. All Prime 9 shifters take advantage of the 9-speeds 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 wont have to constantly adjust your set-up.