I have the staywell Infra-Red 500 cat flap!   it works really well, we
changed it from the magnetic type as it wasn't working very well with our
cat.
infra red one is good but we found it used too many batteries, so we changed
it to mains, you can buy the power supply, but we could not find it locally,
so my partner made his own up... works perfectly :-)

Hi,

I installed a Staywell 500. The manual says the installation in metal doors
is the same as in wood. It differentiates the 500 & 300 series from the
magnetic 400 series, which it says needs to be isolated from the metal.

It works well, better than the magnetic flaps, because the cat activates it
when it gets within 1m, rather than having to put it's neck in a certain
place right in the flap.

The main problems I have encountered is with the collar keys.
(1) If you put the batteries in the wrong way (it's not clear from the
manual), it overheats (see the FAQ at www.staywell.co.uk)
(2) One of my 2 keys stopped working after 1 week!
(3) Getting new ones is hard work. Don't rely on Staywell
(4) If you need to reset the whole kit because it doesn't recognise the
key, do this: take the batteries out of the cat flap for one minute, then
replace (light will flash). Take the batteries out of all your collar keys,
replace them the wrong way, and close the key for 1-2 seconds. Then replace
them the right way again (seems to reset the key) and the key should flash -
then you know it's working (If you just take the batteries out and replace
them in the right way, it won't reset the key). Then just point the key at
the cat flap (which is still flashing) and it should beep. Any other same-
colour keys that you have reset should now work

Good luck!

Sam