Under Armour UA Mountain Pants 2012: For those of us who love our shell pants but don’t want to freeze after 2 runs on the mountain, the Under Armour UA Mountain Pants are ideal. They fit perfectly under shell pants and offer comfort and warmth when you need it most. The sueded ArmourFleece® in combination with Under Armour’s famous ColdGear® tech is like putting Bobby Brown on skis: a perfect fit.