Waterproof fabric uppers. DWR-treated upper is water and stain resistant. Merrell Conductor Fleece treated with Aegis(R) provides warmth and comfort, in harsh winter conditions. 80 grams of PrimaLoft® Insulation treated with antimicrobial solution, for breathability and comfort. Insole provides cushioning and arch support. Vibram outsole is durable, slip resistant, and shock absorbent.