About Madshus Nanosonic Ski Boot: At Madshus we do a full line of skis, boots, and poles. This is one of our new skate boots we’ve been doing. This one’s brand new last season for us. It’s a full on carbon skate boot, top of the line. We also do classic this year—soft shell outer, very flexible, very comfortable. It’s also carbon reinforced in the heel. So skate and classic. New this year is what we call the PUC. This is a universal boot. It is a combination between a skate boot and a classic boot. It’s becoming quite popular at the race end for duathlon style racing.