UGG's Classic Birch II blends waterproof nubuck with inverted sheepskin for a slip-on boot built for winter. The dark brown exterior features visible stitching and a rear tie detail, while the soft sheepskin lining delivers thermal insulation. An EVA midsole from sugarcane and a sturdy rubber tank sole provide traction and support. Styled with the iconic heel logo, this is a functional luxury piece for the coldest days.