The vendor acquired this knife from special-effects technician Bert Luxford, who apparently made four variations of the throwing knife concealed in Bond's briefcase in the film. Three of these were prototypes for the one used in the film. The knife, in this lot, apparently didn't fit into the case.
The introduction of Q Branch, the Armoury of the Secret Service, and with it, Bond's gadgetry was a significant developement in the second Bond film. The attaché case was actually based on Ian Fleming's original idea ..In the novel, the case contained a secret compartment and a flat throwing knife hidden in the lining. The film adds a sniperscope (with infra-red lens), ammunition, hidden gold sovereigns, and a tear gas cartridge. All of these devices come into play at crucial times during the film, [the knife being used most effectively in Bond's fight with Red Grant on the Orient Express] and unlike the use of such implements in other Bond films, 007 must here rely on his wits and quick thinking to activate them... As Raymond Benson notes ..The early films' use of gadgetry, for the most part, was clever and amusing; but beginning with 'Thunderball', these contraptions began to dominate the screen and reduce the characters and the stories to simple maniupulators of machinery... Like them or not, the gadgets have become an essential part of the successful Bond formula.