Great for 10 or 11 speed deraileur
If you are going above the capacity of your derailleur than you may require something like this. I have a grx 11 speed 2x deraileur (rd-rx810) and I wanted to use 11-46 cassette but exceeds 42T capacity so using this goatlink allowed me to use the cassette. The product is high quality. Great way to get the extra range from your setup.
Rafiq M.