Premium Watch Band: Made of soft environmental silicone NO bad smell DO NOT fade flexible and durable for long time Comfortable to Wear: Waterproof washable and easy to dry sweat-resistant and smooth to skin ideal for doing fitness and daily wear Easy to Install: quick release spring bars allow you install and remove the strap in seconds Fit to 5.5”-8” Wrist: the short band is 78mm (not counting the buckle) the long band is 125mm suitable for most people. Thickness: 3.5mm Size Selection: the size is the width of your watch lug. Please measure your watch lug width in millimeters (refer to figure 5). Any questions please let us know we will try our best to solve the problem for you