Large stereo tube No. 362 of the field artillery sample of the Optical Plant of the State Agrarian University, 1915

The magnification of the tube is 10X, the field of view is 5 degrees, and the aperture is 25. In the right eyepiece there is an angle-measuring grid of the RIA sample, engraved on glass with divisions in "thousandths". The stereo tube was designed to monitor the battlefield, search for targets, adjust artillery fire, etc. The kit included: the stereo tube itself, a holder, a limb, a tripod (tripod), two light filters, a satchel for storage and transportation, as well as a tripod case. It was supplied to the troops at the rate of one stereo tube per artillery battery, one for division management, and then one for each of the artillery directorates following the hierarchy. Manufactured in Riga, on sequestered (taken under the external control of the RIA Main Artillery Directorate) in connection with the beginning of the First World War at the optical plant of the company "K.Zeiss." It is almost a complete analogue of the BST company "K.Zeiss" model of 1911, produced at the same Riga plant and in Germany on orders from GAU RIA., since 1913.  The external differences between the BST1915 of the year of manufacture and the devices of the pre-war period are the change in the name of the plant in the labeling and painting of the pipe in a protective color.