The Thermal series now encompasses Original series with the 2223 Winter in Rustic Brown Thermal Lined Boot from Blundstone. It's a warm twist on one of Blundstone's more popular leathers. Improves with age! Hi Tops rise slightly higher against the elements, and now add the heat-retaining qualities of pure wool footbeds and Thinsulate lining for a boot that makes everyday sense. 100% waterproof, even the elastics. All-day Blundstone comfort and warm feet, come what may.