My son grew out of these. We were hoping to get couple years of use but only used for 1 winter season. These are great for layering under snow gear or when hiking in cold weather. Product description From all-day ski sessions to snow day neighborhood gatherings, kids need warm gear to keep them outside doing what they love. Our Kids' Classic Thermal Merino Base Layer Pattern Crew uses soft Mid 250 interlock knit, great for layering in cool conditions. Now your kids can be as warm, dry, and comfortable as you are in your Smartwool® base layers. Features •Slim Fit •Crew neck with set-in long sleeves •100% Merino wool fabric made with an interlock knit for enhanced comfort, breathability, thermoregulation, and odor resistance •Flatlock seam construction designed to eliminate chafing •Knit in Vietnam: 100% Merino Wool