Put simply - RoadLink allows you to run a much wider range cassette than would normally be possible on your cyclocross/road/gravel bike. It's ideal for riders who want to switch to the simplicity of a single front chainring, without giving up the gear range a double provides. Also great for riders who want to keep double chainrings but enjoy ultra-low gearing for very steep climbs.
This patent-pending device is optimized for use with ten or eleven speed cassettes in 11-36t or 11-40t ranges. Note that RoadLink is optimized for Shimano rear derailleurs, but works with SRAM and Campagnolo (only up to 36 for Campy please) too.
Vendor: Wolf Tooth Components