The OMEGA is the lightweight close fitting double boot for ice climbers and mountaineers who want greater efficiency and climbing power from their "plastics". For performance and comfort - the OMEGA is built on a leather boot last with a light carbon fiber midsole for low bulk, light weight and greater sensitivity on vertical ice, mixed climb and mountaineering. Soft tongue and ankle cuff boosts comfort and flexibility on approach hikes and for exact foot positioning on technical pitches. Low profile Baltoro sole is compounded for friction on wet rock & ice and has plenty of traction on the trail and for kicking steps in hard snow. New Thermo EVA Liner is seamless and toasty warm for frigid days on New England ice, long back country days in the Rockies and expedition climbing on 6.5 k M peaks in Alaska and the Himal. For a custom fit, liners can be heated in a convection oven per special instructions included. Sold in UK sizes (one size down from US size), ie UK 10 = US11.