The 75mm norm is the traditional norm in telemark: cable binding which brings lightness and flexibility. Most of the people began telemark with this type of binding. Despite the development of NTN and the end of some brands (G3 and Black Diamond), the 75 norm still exists and still has some devotees. They exist with a touring mode. Warning: to use a 75 norm binding, you need a 75 norm shoe (a shoe with a "duck beak")
For several years, 75mm norm was the only telemark norm and brands like G3, Black Diamond, Rottefella, 7TM were the reference for telemark bindings. 22 Designs and Voilé keep producing them.