PVC-Free. In keeping with Madshus" ongoing commitment to protect the winter world, Madshus has introduced the best-fitting and most breathable boots yet, in a totally PVC-Free construction that lessens our impact on the winter world around us * NNN Outsole. Madshus boots use the Rottefella NNN binding interface. * Lacing Fingers. Providing the best-fitting Nordic boots requires a lacing system that secures the entire foot. * MemBrain Softshell Construction. Madshus boots feature MemBrain softshell and hybrid constructions, allowing the boot to comfortably conform to the contours of the foot while providing durability, waterproof protection, breathability, and warmth. * Madshus" Lacing Fingers reach far below the boot"s visible lacing system to the bottom of the boot, securing the forefoot laterally and medially with balanced lacing tension.