May I present to you the British army Number seven. No7 for short. These I'm led to believe were made up and issued to the British Royal Marines to be used on Arctic camps and doing the Arctic warfare cadre. As you can see from the pictures when compared against the SVEA 123, it stands taller and has a more “Beefy” look to it. The stove is made up of a tank from an Optimus 80 mated to the stem and burner from a SVEA 123R. It is then fitted into one of the most sturdy and over-engineered steel cases you could ever imagine. I have seen a few of these stoves over the years and they are quite collectable and work very well. The bigger tank even though it holds the same amount of fluid as the 123R is supposed to give a burn time of 1 ½ hours where the information on the 123R states a full tank will give 45 mins. If you're looking to buy one then always make sure that the stickers on the stove base are correct because from time to time the outer cases come up for sale on ebay as NOS and some people buy them and make up the stoves from parts, even though they look and work the same it's not the genuine article and you could be paying well over the odds for a Bitsa! Another thing to keep in mind is that because the case is so well-engineered (Heavy) the old British Marine will take the stove out of it's original and put it in a much lighter “Tin plate” Optimus 80 or Optimus 71 case. So again check your stove. I really rate these as users, they are heavy to carry but bomb-proof, if you and a midi pump and cap to the stove then you'll have something that will work in any weather and should last your lifetime at least, if not longer. Si.