The TRX 450R stock swingarm has no rear chain guide. The chances of throwing a chain and breaking your engine case is a real possibility without a proper chain guide. Here is your solution. The TM Designworks one-piece plastic shell is combined with two special Powerlip Rollers for performance. Will accept the TM Designworks 1/4" skid plate (sold separately). Note: Should NOT be fitted with any stock or aftermarket skid plate.