A small rubber band with an impressive list of claimed benefits, but which stack up?
Better balance - haven't noticed any effect
Improved blood flow - nothing noticeable
Improved strength - no, this isn't going to replace exercise - get down the gym or go out running.
Better sleep - so far, seems to work (whether this is a genuine effect, or psychosomatic / placebo effect, who knows?)
It's well made, comfortable, stylish and might just help, even if you're just tricking your mind.
One thing - it weighs nothing, so delivery charges should be minimal. In fact you can purchase from an online auction site for this price and free delivery.