The DM-DO-D2315NVF is a plastic case dome, with a 3.8~9.5mm Auto-Iris Vari-Focal lens that allows its user to view the 550 TV lines of high resolution (powered by a 1/3” Sony IT CCD chipset) in crystal clear images. Where most dome cameras are 2-Axis, the 3-Axis feature included in these models also insures that you can maneuver the camera at an angle that would be most beneficial when viewing images from these cameras. The Digital Slow Shutter (DSS) along with the 0.3 Lux rating allows for clearer images during nighttime recording. The DSS feature allows this camera to filter out many of the light disturbances (noise) that may obstruct nighttime recording.