Features: High strength aluminum bike headsets expander reduces weight by 40% vs steel version while supporting 30kg loads, features a double sleeve expansion system for tool without installation within 15 second. Integrated 5mm internal cable routing port accommodates brake/shifters line seamlessly, with anodized corrosion resistant surfaces enduring 100 hour salt sprays tests for long terms performances in harsh conditions. Essential for road cyclists, mountain bikers, and DIY mechanic pursues light weight upgrades, compatibility with 28.6mm carbon/alloys front forks across 95% of modern bike frame. Perfect for commuters bike maintenance, and professional workshop installations where quick stem fork alignment matter most. This headsets screw's ±1.6mm expansion ranges ensures secure stem clamping without fork crowns damage, combining aerospaces grade durability with bicycles cockpits organization. Specifications: Dimension:5x2.50cm/0.98×1.97in Component:Aluminum alloys Package Includes: 1pc Bicycles headsets Expander note: 1.Please allow 1-2cm errors due to manual measurement, making sure that you will not mind before order. 2.Due to the differences between different monitors, the picture may not reflect the actual color.