When you pay so much money for a cat repellent you expect it to work. I have no doubt that this works and over a period of time, cats have learnt to stay clear of my garden. WHAT'S THE SNAG THEN? First, the device gobbles up two 9V batteries in 7-10 days. Not cheap. Problem solved by buying rechargeable batteries and charger at cost of about £. Snag two. To replace the batteries you must remove four tiny and poor quality screws ; fiddly and inaccurate. Eventually the plastic gives way and it becomes impossible to get a clean fit. Water seaps through when it rains and the baterries are gone. Shame, because this could have been the gadget that many gardeners dream of. What would it take? Make the battery container permanently sealed and get the batteries recharged like other garden gizmos; not rocket science really.