ALTERNATIVE ARMBAND: This is an alternative fabric armband/cuff to hold your tempdrop device. It can be used to replace the original band that comes with tempdrop. | EASY TO USE: Wear the Tempdrop sensor armband on your upper arm during sleep and then sync whenever it's convenient. | ADJUSTABLE: Closure is velcro and there is a metal rectangular ring to help with adjusting. Each armband will come with a sleeve that slides over and covers the velcro overlap and the metal rectangular ring. | SHAPE FIT: The temp drop compartment is stitched to be shaped like the tempdrop so it is not sliding around at night and is completely secure. | SLIDING SLEEVES: Armband is equipped with sliding sleeve. After adjusting the circumference of the Velcro buckle to fit, the sleeve is covered with the Velcro, which not only looks beautiful but also prevents skin abrasion.