The Acerbis chain guide, replacing the original component, guarantees greater impact resistance thanks to the high-strength plastic material. The guide is made in two pieces: the body and the slide, the latter replaceable once worn, also allowing you not to have to disassemble the chain when replacing the slide or the guide itself. The controlled elasticity structure of the guide absorbs shocks and minimizes damage to the chain and crown. Fits: Yamaha WR250F 2020-2021 WR450F 2019-2021 YZ250F 2009-2021 YZ250FX 2015-2021 YZ450F 2009-2021 YZ450FX 2016-2021