for the womens FitFlop sizing guide. Click to learn more about the biomechanically engineered, ergonomic FitFlop footbed. The FitFlop Siren Leather Espadrilles are a cozy little slip-on with a smooth leather construction, elastic topline, and braided jute trim. Soft leather and textile lining with a cushioned footbed for all-day wear. Lightweight and flexible synthetic outsole. Imported. Measurements: Weight: 7.4 oz Product measurements were taken using size 10, width M (B). Please note that measurements may vary by size. Weight of footwear is based on a single item, not a pair.