Complex sentence: The overlapping flaps and four buckles that close them are almost universal on modern designs, producing the stiff cuff that allows excellent control by transmitting even the smallest lateral movements of the leg to the ski.
Split into simpler sentences: The overlapping flaps and four buckles that close them are almost universal on modern designs. When closed, the leg and cuff forms a single unit that is very stiff, allowing excellent control over the ski by transmitting even the smallest lateral movements of the leg to the ski.