The Twister Throttle Tube from ProTaper is constructed from quality anodized billet aluminum. The sealed radial ball bearing and polymer bushing allow for a consistent and smooth throttle operation while a knurled grip mounting area ensures a vice-like grip bond. The ProTaper Twister Throttle tubes are used by top-level pro teams and riders world wide. Twister Throttle Tubes are compatible with all ProTaper handlebars and Renthal 7/8 in. handlebars with the standard bearing insert.