Review on 🚴 IQ Labs Chain Guide Model 2 MTB Tensioner Custom Design by Cody Mckechnie

Basically it creates an external support for the chain. 10/10 recommend. My Marlin 7 came with a crappy clutchless derailleur and the noise was unbearable and I finally started looking for a fix and it made it perfect. It doesn't really add much resistance, but of course it will wear out over time and need to be replaced. But now it's going to be awesome! (Looks ugly, but if you want a pretty one, just buy an expensive chain guide)