The LM308IR 3.0-8.0mm varifocal IR (infrared) auto iris lens is designed for use with Day/Night cameras. It provides color crisp images in daytime and B / W images at night. IR corrective lenses allows for sharper images to be produced under various lighting conditions. This is achieved by eliminating the shift of focal points in both the visible and infrared light. Using IR corrective lenses, rays from both spectrum can be focused onto the same plane.