2 internal aperture stops
Date: 1875-1900
Inventory Number: 2007-1-0360
Classification: Diaphragm
Dimensions:4 × 4 × 0.7 cm (1 9/16 × 1 9/16 × 1/4 in.)
Description:
This is a pair of brass aperture stops of the sort inserted into a tube. The openings vary in size.