This neat and well-made little engine was the final entry in the British "1/2A revolution" of 1959-1960, which saw no fewer than four .049 glow-plug models appear on the British market within a very short time-span. It was manufactured by John Rodwell Ltd. of Hornchurch in Essex, England, and was marketed by KeilKraft.
In many ways, the Cobra .049 was the best of the four British 1/2A glow-plug engines from that period. Although it appears at first glance to be a Cox clone, it actually embodies a considerable amount of original thinking, primarily directed towards making it more acceptable to the British market as it then existed. The original version was quickly followed by a slightly modified variant having a somewhat higher performance.
Sadly, the appearance of so many competing models all at once quickly resulted in over-saturation of the market, the result being that only the anaemic D-C Bantam survived, mainly because of its very low price (which was amply reflected in its pathetic performance!) The Cobra was among the casualties, being marketed somewhat half-heartedly for only some two years or so beginning in late 1960. It appears that some 5000 examples may have been produced during that period.
For the full history of the Cobra .049, see my earlier article which may still be found on the "Model Engine News" (MEN) web-site.