UK sizing. The sturdy soles and great ankle support of the Z-11S boots make for easier going in rocky terrain, whether carrying a heavy backpack or not. Especially in Nordic terrain, where moisture is abundant, their taller shafts reduce hassle in stream crossings. Despite their long shaft, they are not as heavy as you might think. This is partially thanks to the Cordura panels used at the rear part of their shaft. - Completely waterproof: a Gore-Tex liner keeps water out - Surface materials: high quality 2.2 mm nubuck leather and Cordura textile - Polyurethane Monowrap midsole - Lowa Cross Duty outer sole - Made in Europe Lowa does not use PFC chemicals in any of their products. You can print [Lowa's size guide](https://backend.lowa.com/media/pages/279dbaf5-f17d-8f8e-f346-2fa87f33af08/f5824c15-4898-7842-05dc-fc1c15437963/67d595c7-df97-d740-ea02-47a08f43b1c9/adae9d706e-1705483145/size_sheet_uni_en_08_21.pdf) and use a credit card to measure your foot. The card is used as a spacer