Wheels Mfrg Replaceable Derailleur Hanger Dropout 144, Trek MTB 2010-Present

From Wheels Mfrg:

• Upgrade or replacement rear derailleur dropouts; stiffer and more rigid to improve shifting performance
• CNC machined from solid 6061 aluminium to exact tolerances
• Stiffer than any original equipment hanger which improves shifting performance
• Still breaks before your frame does to perform its main function
• Direct replacement for original equipment with guaranteed fit
• Black anodised for extra scratch and damage resistance
• Laser etched for easy part identification