On Thu, 2 Dec 2004 21:00:45 UTC, (Gel) wrote:

Kidde ones on TLC website use a mounting plate [provided with alarm];
this has knockouts for standard dry lining boxes[round or square];
this of course assumes you have the ceiling void access available to
you.

The ones I mentioned from CPC:

SR00837 - pattress
265048 - ionisation alarm
265055 - optical alarm
265054 - heat detector

All made by Firex.

--
Bob Eager
begin a new life...dump Windows!