Brilliant device to save water when showering. I've had one since my last eye watering water bill and can highly recommend. Simply push the button to restrict the water flow to a trickle whilst lathering yourself and then push the other way to turn the water flow back to normal.
If on a water meter should make a significant saving of cash over the months.
2 pounds postage but if you buy other water saving items on the site you can make a saving there too!