Just came across this today, and never saw anything quite like it before. Blued metal box about 5 x 9", stamped "US" on the lid. There are no other markings on the box or contents.
Contains a brass oiler, a brass container for - patches? (There is nothing in it now.) and 10 each cleaning rods, brushes, tools. The brushes are .50 diameter, and have an unusually short thread. The L shaped tools have a screwdriver blade on the short end. The long end is cylindrical, .097 dia. and flat on the end.
My first thought was that it was a cleaning kit for 10 .45 cal pistols, but the brushes are wrong for that use, and the L tool seems to serve no purpose on a .45 pistol or revolver.
Does anyone know the purpose of this kit?