Hat clip strap is safe even when blown by the wind. Keep the clip on and keep it from being blown away. The length can be adjusted steplessly, so it can be used by children. The small clips are made with a soft rubber-type cord that is hard to notice, so it wont hurt your skin. You can also use it as a mask strap if you bring the string to the back. It is convenient for you to drink a little or when you go out without someone around you. Clip Width: 1.2 x 0.4 inches (3 x 1 cm); Length Adjustment Parts: 0.7 x 0.6 inches (1.8 x 1.4 cm); Size S: 8.7 inches (22 cm); Size M - L: 10.8 inches (27.5 cm); *There may be slight individual differences. All parts to make are made in Japan. The clip is recommended with a thickness of 0.04 - 0.16 inches (1 - 4 mm). It may be damaged if pinched forcefully.