product information Name: Fitbit Alta Smart Bracelet Material: TPE + TPU synthetic environmental protection material manufacturing Process: the use of zinc alloy die casting material, the surface plating injection treatment, all the materials on human skin without injury, environmental safety, not allergies. Features: wrist strap design ergonomic, durable, soft and moderate, very comfortable to wear, Compatible with the original Fitbit Alta smart bracelet WRISTBAND Tips: 1, the product does not contain the main movement. 2, please the corresponding color to buy, there are size distinction, thank you