CCTV Camera Lens - Why Iv changed mine from 4mm to 2.8mm Hikvision - YouTube
What's the difference between 2.8mm & 3.6mm lenses?
Hikvision DS-2CD2066G2-IU(2.8MM)(C) 6MP AcuSense 2.8mm lens Darkfighter mini bullet camera with IR & built in mic
2.8mm CCTV Lens Security Camera Replacemnt Focal HD Lens Mount M12 IR Lens for 1/2, 1/2.5, 1/3, CCD or CMOS Sensor Lens : Amazon.co.uk: Electronics & Photo
CCTV 2.8mm 3MP HD Board Lens 115 Degree Angel Camera Lens Security Replacement | eBay
5MP Full-Colour View Starlight CCTV Camera with Built In Mic Fixed 2.8mm Grey