Derailleur Hanger Extender Bike Rear Derailleur Mech Hanger Extension Frame Rear

Designed for 10-speed and 11-speed cassette with large cassettes (42T-50T). When upgrading to a larger cog, the rear derailleur may struggle to shift onto the largest sprocket. This derailleur hanger extension allows for smooth shifting onto the largest cog, while also relieving the spring tension on the rear derailleur.

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