This SOS Earthquake Emergency Whistle is an adjustable hook and loop closure for a custom fit, Fit both left and right wrists. Breathable material reduces the growth of odor-causing bacteria. .This may not hurt your skin, and it is more comfortable to use.
Material: 60% Neoprene, 35% Nylon, 5% Lycal
Size: Free Size, Fit for wrist Circumference 12-22cm（4.7-8.7"）