Wolf Tooth 25mm long B-Screw for adapting old deraileurs when using a GC cog

The Wolf Tooth 25mm long B-Screw is a great solution for adapting old derailleurs when using a GC cog. It provides an extra 25mm of distance, making it perfect for derailleurs that need a little extra clearance for a 40 or 42 tooth cog. It is an M4 x 24mm screw that will give you that extra little push you need for your derailleur to clear your larger cogs. This product is a must-have for anyone looking to upgrade their drivetrain and get the most out of their bike.