Wheels Manufacturing replacement hangers for use with Shimano Direct Mount rear derailleurs. These hangers replace both the standard hanger and the Shimano B-Link, offering a simpler, yet stiffer attachment of the derailleur to the frame. Additional benefits are quicker wheel changes and more precise shifting. Currently, Specialized, Kona, Trek and Donnelly do not offer direct mount hangers for these frames. Wheels Mfg is your only source for these hangers! Features: CNC machined 6061 aluminum Black anodized finish Attaches to frame with (1) M4x20 Flat Head Screw For use with Shimano Direct Mount derailleur Compatible with the following bike models: Donnelly C//C (w/ Shimano Direct Mount RD) - All G//C (w/ Shimano Direct Mount RD) - All Kestrel TERX (w/ Shimano Direct Mount RD) - 2018+ TERX (w/ Shimano Direct Mount RD) - 2019-2020