Manual-iris lenses are applicable to places where a small variation in lighting takes place. All of our lenses with manual irises are available in CS mount. Focal Length f = 2.8 ~ 10mm Aperture Ratio 1:F1.4 ~ close CS Mount, 1/3 inch Format Camera Focal Length f = 3.5 ~ 8mm Aperture Ratio 1:F1.4 ~ close CS Mount, 1/3 inch Format Camera Focal Length f = 4.0 ~ 16mm Aperture Ratio 1:F1.4 ~ close CS Mount, 1/3 inch Format Camera Focal Length f = 5.0 ~ 50mm Aperture Ratio 1:F1.7 ~ close CS Mount, 1/3 inch Format Camera