Strap In: Kids love an easy-on, easy-off bootie with a strap they can handle themselves. The SOREL® KidsWhitney II Plus Bootie WP has all that plus a cozy lining and waterproof construction. Crafted from nylon upper, fleece lining, and insole, this pair of boots features waterproof nylon upper with PU coated synthetic overlays. Hook-and-loop closure on lateral and medial side, microfleece lining, and waterproof bootie construction.