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MITTEN HANDCUFFS SECURE CRIMINALS
Only the tips of fingers and thumbs protrude from handcuffs of a new style, invented by a former member of the Canadian Mounted Police, and shown above. Each of the metal gloves is hinged in two leaves equipped with locks. The mitten-shaped handcuffs were devised by the inventor in the belief that the ordinary type makes it possible for a desperate criminal, being transported overland, to attempt to grasp his captor’s gun or attack him with the hands. - MITTEN HANDCUFFS SECURE CRIMINALS, Popular Science (Oct, 1933) - via Modern Mechanix