 Initially Fraser-Smith supplied clothing and standard props (from second-hand sources) for SOE agents working behind enemy lines, but SOE directives and his taste for gadgetry led him to develop a wide range of spy and escape devices, including miniature cameras inside cigarette lighters, shaving brushes containing film, hairbrushes containing a map and saw, pens containing hidden compasses, steel shoelaces that doubled as garrottes or gigli saws, an asbestos-lined pipe for carrying secret documents, and much more.Directed to make copies of a new type of Luftwaffe life jacket, he made discoveries that were subsequently incorporated as standard in RAF "Mae Wests", including the use of a compressed air cylinder for inflating the jacket and a pouch filled with a powerful fluorescent dye for spotting of a downed airman at sea.In an example of lateral thinking, Fraser-Smith used a special left-hand thread for the disguised screw-off top of a hidden-document container; he suggested this would prevent discovery by the "unswerving logic of the German mind", as no German would ever think of trying to unscrew something the wrong way.