Feature: 1. Main Parameters: CS mount lens, resolution 3MP, focal length 4.0mm, format 1/2in, relative aperture 1.2, field of view 76 degrees. 2. Easy to Focus: The focusing ring, which is easy to hold, provides very accurate focusing for high quality recordings. 3. High Image Clarity: CCTV lens has manual focus and adjustable aperture, no lens shadow, no vignetting, good image quality. 4. Premium Material: High quality aluminum alloy shell, temperature resistance, can adapt to different outdoor environments. 5. Wide Application: CS mount lens can get more clarity, focus, suitable for home security system and video surveillance etc. Specification: Item Type: CS Lens Material: Aluminum alloy Focal Length: Approx. 4.0mm/0.16in Format: 1/2in Relative Aperture (D/f'): 1.2 Interface (Mount): CS Field Of View: 76° Back Focal Length: Approx. 12.5mm/0.49in Aperture: Manual/Lock (W/Lock) Resolution: 3MP Close Up Distance: Approx. 0.2m/0.66ft Size: Approx. 30x32mm/1.18x1.26in. Package List: 1 x CS Lens Note: The optical coating is very important for the imaging of the lens, and it needs to be handled with care to avoid scratching the coating.