The light and low-profile Rottefella NNN-BC Auto binding is great for skiers who want the convenience of a step-in binding and the added strength of the BC binding for mixing some off-trail skiing into their day! Rottefella's Back Country bindings are especially designed to perform in difficult conditions, where durability and control count the most. Innovative technologies, like sturdy closing mechanisms and wide binding plates, contribute to the optimal combination of performance, durability and comfort, for demanding expeditions and long trips. The Rottefella NNN-BC Auto fits all Rottefella NNN-BC soles but DOES NOT accept NNN Touring soles so look for the NNN-BC logo on your boot soles if you are uncertain. NNN-BC Auto bindings are wider for more stability and stronger than regular NNN bindings to withstand the rigors of off trail skiing. The step in design has an audible clip when you're locked in and is easily releasable with your ski pole tip. The integrated "Steering ridges" ensure maximum ski control and the flat heel plate provides stability in off-trail situations. The Rottefella NNN-BC binding system is the only heavy duty back-country system binding currently on the market and works with a wide range of boots from simple light touring boots to the Alpine Alaska Heat heated all leather back-country boot.