I bought 2 more wireless repeaters on-line only to find that they were not compatible with my existing repeaters. This could only be established by putting one in the socket and then seeking help when it wouldn't work. Now Argos are refusing to refund me because it's '.used'. I could understand if it were food or some types of clothing or jewelry I could understand it but when its just an electronic plug that has been plugged in once..................Clearly doesn't pay to be honest either. I will never use them again and now I've seen Argos' review rating I wish I'd checked it before.