The length of this watch strap is fixed and does not have an adjustable buckle. It is suitable for wrists ranging from 6.10 '' to 8.67''(15.5cm~22cm). For wrists that are too small, choose an L size strap. After assembling the watch, it will move on the wrist, affecting wrist movement. Therefore, please confirm the wrist size The outer ring is made of layers of lightweight nylon fabric, and the inner ring is made of high-quality and stretchable nylon rope. The entire lightweight strap reduces a lot of pressure when worn on the wrist, providing a more comfortable experience This strap is compatible with the iWatch watch series 9 8 7 6 5 4 3 2 1 SE Ultra and comes with a compatible connector. Simply slide to install a new strap The watch strap comes in S and L sizes, with fixed lengths. The S size is suitable for wrist lengths ranging from 5.11 '' to 6.10 '' (13cm-15.5cm), while the L size is suitable for wrist lengths ranging from 6.10 '' to 8.67 '' (15.5cm-22cm) There are 7 different patterns to choose from, a single nylon strap, a variety of options, simple and durable nylon replacement strap, suitable for different styles of clothing to match Comfortable hair ring nylon strap, L size, has good stretchability and fixed length, suitable for wrist wear at 6.10''-8.67 (15.5cm~22cm). The appropriate watch strap size allows the strap to be fixed in one position of the wrist without moving. Just snap the connectors at both ends of the strap into the watch and you can wear it.