Oxygen tubing 'rope'

A relative was sick & used oxygen. I played with some old tubing, noticing it could be knotted, like rope. It's stiffer than rope of the same diameter, but isn't rough so it doesn't cut in the skin. The friction between tubing makes knots very secure. I enjoy tying my scrotum and testicles. O2 tubing is especially suitable for tying the balls. I use a 'bottle knot' around the top of my scrotum being gentle to the tender skin.

Great idea use what you can. I use to use old phone charging cables they worked great for tieing my balls because it was just enough to get the job done

For tieing balls, I use soft shoe laces. They tie well and don't chafe.