Design idea Upgraded TPU bands in a take-on, lightweight structure to fit vivosmart 3 / vivosport. New Performance Unique structure design with strap turns out an elegant look and works reliably. Quality materials Made of premium TPU, breathable and washable. Soft and comfortable feel for all-day wear. Significance Anti-allergy, heavy-duty, lightweight design features always-on 24/7 wearing, improving the precision of enhanced recovery timer and workout recommendations based on your sleep and wellness data