The Kay SL combines all the advantages of the Birkenstock classics Tokio and Boston into one model. The top instep strap can be folded back when needed, serving as a heel strap for additional support. The Super outsole is slip-resistant, rolls perfectly, and is also oil- and grease-resistant. Its EVA midsole cushions every step. This high level of flexibility and surefootedness is especially sought after in the medical field. All Super outsole models are tested for slip resistance according to EN ISO 20347:2012 standards. The shoe features an anatomically shaped cork-latex footbed, a Super outsole with a cushioning midsole made of lightweight, flexible EVA plastic, and a slip-resistant oil- and grease-resistant rubber outsole. Slip resistance is tested according to EN ISO 20347:2012 (SRA category). ko-Flor is made from an easy-care, hygienic PVC material, lined on the inside with a soft, breathable layer of fleece. Individually adjustable metal pin buckles and the skin-friendly, flexible leather insole gently conform to the foot´s contour. The open-pored and highly breathable surface ensures a pleasant foot climate even during intense physical activity. A particularly deep heel cup supports the heel tissue and keeps the heel bone stable in its natural position, providing nearly the same support as a closed shoe. The heel bar activates the calf muscles, stabilizes the rear foot, and improves stride guidance and coordination. Width: narrow. Size: 43