M.R.D. Foot tells a story of an underground agent forced to transport a B-2 wireless set (radio) through a railway station in which German forces were conducting random checks of luggage and personnel. The radio which the agent was carrying was a distinct size and shape and thus easily recognizable to alert police forces. The underground operative, realizing the precariousness of his situation, initiated a cunning security measure he presumed would reduce his risks.
He, reached a big terminus by train; carrying only his B2 in its little case; saw a boy of about twelve struggling with a big one; and said genially (in the local language) “Let’s change loads, shall we?” He took care to go through in front of the boy; there was no trouble. Round the first corner, they changed cases back. The boy said “It’s as well they didn’t stop you; mine’s full of revolvers.”
Foot, MRD, Resistance, (New York, McGraw-Hill Book Company, 1977), as quoted in: Underground Management: An Examination Of World War II Resistance Movements by Christian E. Christenson