Spank Spike 25/30 Direct Mount Bicycle Stem - E06SD250 2D forged, micro grain refined, 6-Series alloy Two direct mount bolt positons: 25 or 30mm extension Included Snap-Fit top cap is sealed with an O-ring to keep dirt and water out of your steerer Includes 5mm of direct mount stack spacer: when installed the rise increases from 28 to 33mm Wide and chamfered bar clamp diffuses the clamping force and adds rigidity to the bar/stem interface