If you run a single chainring up front, use Paul's Chain Keeper to keep the chain on. Perfect for 'cross or 1X10 setups, the Chain Keeper has a 3-sided chain watcher so even over the rough stuff, your chain stays on the ring. It mounts to round seat tubes and is easily adjustable. And, like all Paul components, it's made of 100% CNC-machined aluminum in his California workshop.
Weight: 69 grams
The Chain Keeper only fits round seat tubes.