This boot offers a tapered, 8mm, high density Nylon®, that provides a smooth flex and protection throughout the boot. This allows for new-matic crampon compatibility and long lasting consistent flex. The 2.8mm Idro-Perwanger leather upper is ideal for water repellency, breathability and durability. An SBR Aircushion sole provides cushion and helps insulate from cold or hot climates. Perfect for light duty mountaineering, heavy hiking and backpacking or various types of outdoor work situations where you need durable support and all-day comfort. This boot runs 1/2 size small. The large majority of customers go by this guide.