This key fob wristlet hardware can come in different widths though, so you need to measure the one you bought to determine what size your wrist strap should be!
You can just fold the short ends towards each other and measure it against your wrist and how you would want it to fit when “wearing” it.
If you are using one wide piece of quilted scrap then fold it over the right sides together before sewing.
Using this hack, you’re going to turn the tubes right side out using a safety pin and a chopstick.