Super ventilation, can almost pass as a sandal. This part is actually but a fiddle when umtritt patented Risthalterung a slipper. Simply ingenious and comfortable to wear. Be careful with the size information: Information totally disagree. Normal shoe size 45, ordered in 45 2/3, as read recessions and the criticism was already more often. Did not fit, much too small. Immediately returned and ordered in 46. The fit.