To ride aggressively, you need strong tunnels that can handle your every move. The Ski-Doo Tunnel Reinforcement accessory provides extra support and boot traction, adding strength along your running boards. Machined aluminum extrusions allow you to dig your feet in. Additional strength and traction along the running board. Machined aluminum extrusions. Colors to add some style. Provides more support and boot traction for aggressive riders. Compatible with tMotion Adjustable Limiter (860201861). Does not fit with Remote Limiter Strap Adjuster (860201855 and 860201496). - REV Gen4 Summit X with Expert package, Summit X & Freeride 154”/165” with tMotion Adjustable Limiter Strap (860201861)