The Wild T3 model of the second-order theodolite was produced between 1934 and 1948 and was mainly used for precision measurements. The instrument is the most precise optical theodolite in the University of Ljubljana, Faculty of Civil and Geodetic Engineering collection. Patented by Heinrich Wild in 1921, the modern design is also a feature of this instrument. The cylindrical axis clamped to the detachable base, the ball bearings, the centric alidade toric level, the optical plummet, the glass circles and the reading by means of the microscope at the eyepiece of the telescope are the essential technological improvements derived from the Zeiss Th1 model. The divisions on the horizontal and vertical circles with a graduation unit of 10^c are read using a coincidence microscope. The graduation unit of the micrometer division is 1^cc (0.3'').

The instrument was used for measurements in national trigonometric nets of higher orders, for research tasks, and less frequently in teaching work, mainly for measurements in diploma theses. In 2016, the instrument was cleaned and partially lacquered.