The K4 S has been discontinued. If you're looking for something new, check out the best mountaineering boots for 2020.
Historic Range: $196.95-$395.00
Reviewers Paid: $234.00-$270.00
Awesome boot. It's not as narrow as some would say. I do not have a narrow foot at all and these fit perfectly. Also, the fit around the foot and room in the toe box can be customized by adjusting the removable tongue.
Excellent design and thought went into these. I love them. They are very warm, but at really high and extreme situations you would still want a double boot like the Nuptse, in my opinion plastics are in the past. Besides the Nuptse, these are the best boots I've ever had.
Materials: Benecke CeraCom® industrial fabric upper, 3M Thinsulate- PTFE layer, carbon fiber honeycomb, polyurethane-coated leatherette Midsole: TPU to leather Lining
Use: Vertical Ice, General Mountaineering - Mixed Climbing
Break-in Period: Very Short
Weight: 4lbs 14oz
Price Paid: $270
The best boot for the price, spent a lot of time in Iceland in them and have never had a problem, very warm and great for mixed climbing. The boots makes plastic boots a thing of the past. Spent hours belaying in them in the low teens and never got cold.
Break-in Period: 2 good weeks
Weight: not bad
Price Paid: $234