The catflap was offered at a very good price and arrived very promptly. The flap itself (Staywell infra-red) and the associated key work very well. Incidentally, the information about the flap says the key operates at a 'generous range' and it's a bit difficult to find out exactly what that means. I eventually discovered that it's supposed to be about 40cm and that's exactly right in this case. The flap replaced a previous, magnetic Staywell flap. The dimensions are slightly different and involved enlarging the hole slightly but not a big deal. All in all, extremely pleased.