is a new device for testing global near stereopsis - using the same principle as LANG-STEREOTESTS I and II, it comes with 6 magnetic test cards, each of them containing one 3D random dot stereo object - the range of disparity is between 1000'' and 50'', and the test cards may be placed and shown separately on the double-side red magnetic test panel - test objects are perfectly hidden when viewed monocularly or with horizontally aligned cylindric grid. - suitable for screening for stereopsis, preferential looking (two or three-alternative forced choice task), assessment of stereopsis threshold by staircase method