I am not sure what it is called, but it bolts to a baby bee, golden bee and black widow engine block with needle and reed valve to hook up a seperate tank I see them on cox adds, but no info is there..Hope that I make my self clear.. Much obliged, Bootlegger

Gil
I have an earlier version of that but it has no reed or reed retainer.  Yours if that will work.
Jim

   think he needs the red plastic back late assembly like what came with some of the plastic RTF models like the Stuka and maybe the Corsair.  I believe it was called the model 190 engine.  I fit into molded plastic pockets in the fuselage and used no mounting screws. The white nylon bracket was put out by Goldberg Models and came with a balloon and fuel line for a balloon tank. The bracket was attached by removing the four screws, placing the engine at the position you wanted it at, then the red back plate, then the bracket and then install the four screws. The mounting holes were the same as for the typical BabyBee tank. The illustration shows the rubber band mounted fire wall mount that was first used on the  Goldberg Wizard trainer and I used this to some good success as a kid. I used the Goldberg mounting bracket on the engine that came out of my crashed Cox Stuka and built a Wizard for it as per instructions. The red back plate/MVA will fit any Cox reed .049 crankcase.
  Type at you later,
   Dan McEntee

   PS to add: I just researched a bit and they call this back plate/NVA a "postage stamp" back plate.  The back plate that pmackenzie points out will work also and you can orient the cylinder any way you want to. It is referred to some times as a "horse shoe" back plate and it has mounting holes in it. I think both require the type of needle valve that they came with and not too sure if any others will swap out and fit .