1. Comfortable and Breathable: The soft replacement strap is made of Cashmere + zinc alloy material, fitting snugly around the wrist without leaving marks. Its excellent breathability ensures no sweat buildup even during prolonged use, perfect for sports and daily wear. 2. High Elasticity and Durability: The sports wristband features a woven Cashmere structure with elasticity, adapting to wrist sizes. It is wear- , maintaining shape without breaking, ideal for intense workout environments. 3. Easy Cleaning and Quick Drying: This wrist band can be easily cleaned with water and dries quickly, keeping it fresh and hygienic for frequent users. 4. Stable and Secure: Specifically designed for Whoop 4.0 wearable health fitness activity tracker straps, offering precise fit and preventing loosening for peace of mind during exercise. Color: Black Material: Cashmere + Zinc Alloy Package Contents: 2 x Fitness Band Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.