by Guide Eric Simonson of International Mountain Guides
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Picture: this is my Everest summit shot wearing my 40 below overboots over my Koflachs—I have used this combo on many mountains all over the world and have never had a problem with cold feet! Eric Simonson

Guide Eric Simonson of International Mountain Guides has this tip to help have happy feet on a climb: He keeps a set of socks in a sealed packed bag, specifically to keep unused until the final summit day.  This way you start out with a fresh, clean and warm set of socks.  This small tip really makes a difference!

When asked to give some thoughts about socks he said: “Ask ten climbers, and I am sure you will get ten different opinions!  I have tried a lot of different sock combinations over the years, trying to find what works the best for me.

For the past fifteen years I have used exclusively the ThorLo Level 3 Mountaineering Sock:  This is the only sock I ever use.  I do not bother with any kind of “liner” sock.  When I am trekking I wear one pair and when I am wearing my climbing boots I wear two pairs.  My Koflach climbing boots are fitted to allow enough room for wearing two pairs of these heavy socks.  I want thickness for insulation, padding and shock absorption.  I have worn this combination for hundreds of ascents of Rainier, for Mt. Everest, Mt. Vinson, and everything in between.   I bring plenty of pairs of socks on a big expedition.  I also bring some detergent so I can hand wash socks at base camp.  Once you wear them a lot, they get all greasy and don’t insulate as well.For summit day I like to save a couple pairs nice and clean, in a plastic bag.  That way I know I will a fresh socks for up high.  I like to change my socks as soon as I get into camp in the afternoon.  Then the dry socks suck some of the moisture out of my boots while I wear them around camp.

Then during the night, I continue to wear these socks to bed and they dry out overnight. The ones I wore during the day, I hang up if possible to dry. If this is not possible, I unzip the leg zippers of my fleece pants and lay the damp socks along my legs, one on each side, between my longjohns and my fleece pants during the night, where they will dry out. Dry socks are gold and you need to keep your feet dry to keep them happy!! In my opinion, this is the secret to warm feet.” Eric Simonson

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These socks have been vacuum packed into plastic bags. Completely waterproof and take up less room to pack.
A vacuum packed pair just for summit day!