In the depths of winter (sometimes Spring and Autumn) we could all do with a little more warmth. The neoprene lined "Iso" boots and the Outlast technology ensures we stay toasty!
Neoprene is used for diving suits and is without doubt the best insulating material known of today. It is a highly techinical material made from microcellular polychloroprene rubber foam that has been lined with polyamide...however some people have naturaly warmer feet than others and may find that the ISO 's are unsuitable for them as it causes their feet to overheat and perspire.