Birkenstock Birko Active Insole (Unisex) - BlackBirko Active Outdoor Fun, the breathable footbed insole for mens and womens shoes, combines the insoles of conventional footwear with the anatomical shape of the foot. The foot is supported and guided during walking and running. The shock absorbing material core ensures outstanding comfort on foot, be it in hiking shoes or casual shoes. Anatomically shaped full length footbed with flexible, shock absorbing forefoot Additional support for sports