Genuine Govt Issue Mountain Ski Boot: The Mountain Ski Boot is worn during mountain climbing or downhill/cross-country skiing in temperatures down to 10 degrees Fahrenheit. Ithas a high leather upper in a long vamp design with combination eyelets-and-hooks closure system. The boot is fully lined, except gusset, with black, glove-type leather. The boot has a removable felt insole for bottom insulation. Vibram sole. NSN# 8430-00-458-0279 Boots, Ski Mountain.