Recommended max binding DIN. This is the max din range on the bindings, not what the skier will likely have the DIN set to. For instance, a 165lb skier often gets a binding with a DIN range up to 12 and has the DIN set to 8.
The waist of the ski binding brake coincides with the waist (narrowest width) of the skis. At minimum, brakes are made to be bent out and can be up to 8mm narrower than the skis. At maximum, brakes can be 12mm wider than the skis. For instance, skis that have a 100mm waist need a 92-112mm brake.
Alpine touring bindings allow you to ski the backcountry with a free heel going up and alpine performance going down. AT bindings open a new world of skiing.