The 75mm vs NTN boot standard debate is over. You choose whatever boot works for you with no sacrifice to power or convenience. Bishop’s BMF bindings work for both styles of telemark boots: 75mm boots which have a “Duckbill” at the toe which is 75mm wide at the pin line and are asymmetric, having a dedicated left and right binding/ski.  NTN (New Telemark Norm) telemark boots have a toe that is similar to alpine touring boots with a short alpine style toe and both a back heel and a “second heel” or “duckbutt” that is under the arch of your foot. 

Bishop’s BMF telemark ski bindings can be used for either boot style by simply switching out the toe cage. The binding has the same power and step-in convenience to the back, “real” heel of your boot with either style boot. BMFs attach to the entire boot, front to back, instead of just the front end like some flimsy cross country ski binding. You aren’t cross country skiing. No spandex allowed. You’re shredding.

Other NTN bindings attach to the Duckbutt, which is located under the arch of your foot. BMFs attach to the back heel which transfers more force from the boot to the ski.  In nerd speak, the longer lever arm of the BMFs gives you a higher mechanical advantage.