The SLA-M2890PN CS-mount P-Iris Varifocal Lens has a focal length of 2.8 ~ 9mm, and is designed to be used with 1/2.8", 3Megapixel sensors. The Precise Iris (P-Iris) feature optimized the depth of field to produce consistent video resolution and quality, while helping the camera to adjust to changing light levels. The IR corrected lens ensures day and night performance is crystal clear.