Commonly used in team sports like soccer or football to identify the team captain on the field.
Here's some information for shopping for a similar item:
Product: Captain's armband, typically made of elastic material like nylon.
Features: Often high elastic, easy to wear, and may come with adjustable fasteners like velcro for a secure fit.
Colors & Design: Available in various colors (e.g., yellow, blue, red) and may feature the letter "C" or the word "Captain".