The brush-scribe-lens was intended to aid the astronaut in observing and marking hand-sized specimens of lunar rocks. The brush-scribe-lens was carried on Apollo 12 and 14 as part of the tool complement for the small tool carrier. References about the use of this tool on the moon are scarce and it is likely that it was not actually used by the lunar astronauts. This particular unit was not flown and was likely used for training. NASA transferred it to the Smithsonian in 1974.
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.