Used for years by our staff in cold weather, these add significant warmth. The pile on the inside lining traps warm air and the outside is windproof. The sides are reinforced against crusty snow and the sole is made of rubber coated glass fibre for durability and anti-slip.  Side zip entry and velcro cuff make these easy to get into. 

These fit both SNS and NNN binding systems.  If you have Salomon's Pilot system (two bars), there are four small holes in the sole of the boot warmer - just cut out the square to fit the second bar.