Rotefella NIS-NNN Xcelerator Skate 2.0 Binding. This is the racer’s choice binding! This lightweight racing binding is lighter, more durable, and a more secure fit than the Performance Skate. Fits all NNN-compatible boots (including Prolink and Turnamic). These bindings only affix to skis with an NIS plate (Nordic Integrated System)(not included). Binding are able to be fine-tuned by adjusting the binding (w/ a simple key included) forward for more control, or backward for more glide. Dual flexor system provides amazing control and balance of ski tip. Wide platform for stability and control.