Made in traditional style, these boots boast a high quality leather shaft and a 100% waterproof rubber lower. The manufacturer mentions -40ºC as the lowest using temperature, but people's feet and situations vary massively - don't consider this a promise of being toasty warm in such cold conditions. - Wide last - Heat-MX insulating liner is detachable for easy drying - Moisture transferring liner - Lower: waterproof, pliable synthetic rubber - Sole: synthetic rubber - Weight: 815g/pcs The leather is manufactured in a gold-rated tannery, meaning the use of water and energy, as well as waste control is on an excellent level.