Description: 【Wide Compatibility】: This derailleur hanger extender is designed to be compatible with a wide range of cassettes, from 40T to 52T mountain bike cassettes, to 34T to 42T road bike cassettes 【Enhanced Shifting System】: By extending the derailleur hanger by 40mm, this derailleur hanger extension effectively prevents interference between the guide wheel and the large gear, ensuring smooth and stable shifting performance 【Aluminum Alloy Construction】: Made of lightweight aluminum alloy, this bike rear derailleur hanger extender is CNC machined, with excellent tensile and torsional resistance, making it a reliable choice for long term use 【Adjustable Design】: The adjustable design of the bike derailleur hanger extender can easily adjust the front and rear angles to accommodate different cassette sizes and speeds, making it easy to install larger cassettes 【Lightweight Construction】: This bike frame tail hook uses a hollow cut design to strikes a balance between strength and weight, making it perfect for competitive competitions or long distance cycling adventures Specification: Material:Aluminum Alloy Compatible: 34T-52T Large Sprockets Compatible: Mountain 40/42/46/50/52T Sprockets Compatible: Road 34/36/40/42T Sprockets   Size Chart: 6.3cmx2.3cmx1.14cm/2.48inchx0.91inchx0.45inch Package Includes: 1 Bike Derailleur Hanger Extender 1 Screw Note: Please allow slightly errors due to manual measurement and different monitors.