I'm surprised to hear that this fuze is so rare nowadays. A lots were dropped on Germany in the beginning of WW2. It is now more than 80 years since its inception. British colonial forces tested it on live subjects in the 1930s in Waziristan according to the old colonial doctrine "Shock and Awe" to demoralize the tribesmen, when bombs, that seemed to be duds, exploded suddenly. That first model, sticking out a long way from the back of the bomb, was countered, in Germany, by a small charge placed on it, that bent the long fuzetube and made it unworkble. This was countered by the later shortened versions that disappeared inside the bomb. This was much more difficult to defuze and has cost the lives of quite a few EOD men in the last 70 years.