Strafor industrial metal shelf 1930s

Rare strafor shelf circa 1930 from the strasbourg municipal library. Completely removable, this shelf has a clever system of racks for adjusting the shelves. This shelf from strafor (strasbourg) was designed by robert lipman at the end of the 19th century. Materials: khaki-colored iron, object entirely preserved in its own juice, traces of original paint use and very superficial rust... The depth of the shelves varies between 20 and 30 cm.