MRP S4 Bashguard
This is a great guard and not too expensive. Works much better and lasts much longer than those stupid frame mounted guards. The MRP S4 chainguides with the rollers (different product) are also bombproof and awesome.
I replaced my mangled big chain ring with the 32 tooth sized bash ring. It was simple to install and included all hardware, instructions, and torque specs. It is lighter weight than the chain ring it replaced and has already survived numerous hits without issue.
Used on my FR bike for a while. Works as advertised!