¡á MODEL/OPTICS *J8901/0.5"optics : High resolution 100 pitch screw 2 point tilt *J8902/ 1" optics : Compact robust design *J8903/1.5"optics : Azimuth - 8¡Ærange *J8904/ 2"optics : No backlash *J8905/2.5"optics : Option : 3 point tilt