As stem height extender to handlebar for comfortable riding Made of aluminum alloy, well-structured, solid and Wide use scope to fit carbon, alloy and steel forks Concealed mount to combine both practical and aesthetic features Comes with 1 types ( 55mm) to meet personal preference. Light weight, quick and easy install. Applicable: Fork riser outer Dia. 28.5mm, Inner Dia. 23.3mm Fits: Carbon fiber, aluminum alloy or steel pipes Screw Hole: M5, Stem M5 bolts can be directly engaged (Bolt not included) Tool: mount with M6 Hex key (Tool not included) Colour:blackandsilver Material:aluminum alloy Size:160 x 23mm Package Contents: 1 x bike tool Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is 1-3cm.