Don't be fooled by the heavyweight Mega grid thermal fleece, because the Under Armour Women's Base 4. 0 Leggings are surprisingly light for the amount warmth they hold. This insulating tight delivers four way stretch for unhindered mobility, quick drying comfort, and odor resistant convenience. The wide performance waistband sits below the hips and resists binding or bunching. Blast down the mountainside with these thermals under your ski shells when the snow is stacked, and then take 'em to the hiking trails when the melt comes, because you're going to need those quad muscles next season.