optimus 123As are the canisters for my old Optimus 721 stove, Gaz Globetrotter stove, and Bluet 200 stove. When canisters become obsolete the stovesI saw a 123123R with a candle flame on the filler cap. I had been called over to fure out why it had a weak flame. I got the cap off and the fuel was boiling. The