Features: Porous design, light and flexible, more breathable Sweat, rain, splash and water resistant, perfect for sports wear Silicone materials, soft and comfortable, environmental protection and non-toxic Built-in quick release pins 2 size for choice: 18mm for Withings Steel HR 36mm, 20mm for Withings Steel HR 40mm 14 color for choice: Black+Pink, Black+Red, Black+Grey, Black+Green, Black+white, Black+Yellow, Grey+White, Grey+Yellow, Red+Black, Red+Teal, Pink+Teal, Blue+White, Purple+Green, Teal+Blue 18mm width Fitment: Nokia Withings Steel HR 36mm Smart watch Huawei Fit Honor S1 Smart Watch Huawei Smart Watch .