[Design idea] Stretchy loop nylon strap upgrades nylon bands in take-on, lightweight structure. [New Performance] Unique stretchy loop design with a distinctive elastic strap turns out an elegant look, and keeps your watch snugly to your wrist for a better workout experience. [Quality materials] Made of premium nylon, breathable and washable. Soft and comfortable feeling brings a good time all day. [Significance] Anti-allergy, heavy-duty, lightweight design features an always-on 24/7 wearing, improving the precision of enhanced recovery timer and workout recommendations based on your sleep and wellness data