Various
Standard certificate given by Instytut Odlewnictwa - a research institute in the field of foundry and metals, founded in 1946 in the city of Krakow.

The institute is supervised by the Polish Ministry of Entreprise and Technology

The institute web site http://iod.krakow.pl

An example of a cover that carries the standard on the "ultimate manhole covers" site. From this lid the picture that appears in the general section was taken.
There are 6 manhole covers in the site that has this standard mark
Click for all the covers with this standard

Click for the rest of the standards in the site

The ultimate manhole covers site

Initiating the site - Eli Zvuluny - Programming and building the site Possible Worlds Ltd. Possible Worlds Ltd. © 2017-2018

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