Remember back in the late 80s there were those keyrings that beeped when you clapped? This is the next generation, taking advantage of wireless technology by fixing colour-coded receivers to items you frequently misplace so that you can ping them from the remote (assuming you can find it). It works at a range of 25 metres including through walls, all for £24.95.
I suggest you clip one to the cat and alarm the neighbours.
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Get Free freeview dongle, test out Telegent interactive TV service
Will this work on my cat?!