Knitted sock sample, made of khaki wool yarn (#4028) for US Army wear during World War I. Civilians were encouraged to knit for the troops; the Red Cross made approved patterns available, and manufacturers made specially dyed yarns available to civilians. Samples of wool and other fiber yarns and knitted articles suitable for US army and navy use were given by important American yarn manufacturer S.B. and B.W. Fleisher, Inc., of Philadelphia, PA in December 1918, along with many samples of yarns for civilians.