Material Aluminum material Made of high strength CNC machined 6061 T6 aluminum alloy, super strong and lightweight. For oversized 31.8mm handlebars Stem riser fits most bikes with 28.6mm (1 ") head tube and oversized 31.8mm (1 ") handlebars. Height Adjustable height and angle The length of the rod elevator is 110mm (length between the center of 2 cylindrical bores), the angle adjustable between + 60 and -60 to match the position of desired conduct. Hex keys included Riser adapter comes with 2 Allen keys, it is convenient for you to screw bolts on the threadless rods and faceplate. Easy to install Just connect the original front fork stem, four bar clamp bolts hold the bar firmly in position. Fits most road bikes, mountain bikes, trail bikes, mountain bikes, BMX, DH, etc. Product description Technical parameter: Material: 6061 aluminum alloy Shank diameter: 28.6 mm (1 / 8 ") Pivot height: 35 mm Handlebar clamp diameter: 31.8 mm (1 / 4 ") Length: 110 mm Angle: + 60 / -60 degrees adjustable angle Color: black Weight: 335g How to install: Loosen the front fork bolts with a 5mm Allen wrench, slide the replacement rod onto the steerer, then tighten the bolts. Loosen the expansion bolt with a 6mm hex wrench and adjust the position of the rod, then tighten the bolts. Center the bars in the stem collar, adjust it to the desired angle, then reattach the faceplate. Tighten each faceplate bolt to complete the installation. Need attention: only suitable for handlebar diameter 31.8mm (1 / 4 ") 25.4mm and other sizes are not suitable. Please check your handlebar size and choose the good model accordingly Package includes: 1 * Adjustable Bicycle MTB Fork Stem 31.8mm