Further to the posts concerning the steel copies if the B1 incendiary made for - but seemingly not used in - the Battle of Britain film, does anyone know the history of the aluminium training aids produced post-war (possibly within the last 20-years but I have no details whatever). I've attached some images and I'd be keen to hear who produced the copies and for whom they were intended. (I assume when new there may have been a spring, striker and other internal components?)