A GEAR DRIVEN MECHANISM INSTALLEDIN A TURRET TO DEFINE DIRECTION FOR A TOW MISSLE LAUNCHER BY ROTATION TO A SELECTED AZIMUTH. OPERATING TEMP -30 DEG TO +140 DEG F. MUST OPERATE IN 100 O/O HUMIDITY AT 84 DEG F AND 2 O/O HUMIDITY AT 125 DEG F. MECHANISM TO SUFFERNO IMPAIRMENT IN PERFORMANCE AFTER EXPOSURE TO SAND AND DUST PER MIL-STD-810. TO ALSO MEET REQUIREMENTS OPERATING AT ATMOSPHERIC PRESSURE ALTITUDES OF SEA LEVEL TO 8000 FT