3mm FL f/2.5, Rugged Blue Series M12 Lens | Edmund Optics
VCC SMB Series Fresnel Round Lens for 3mm T-1 LED, 0.171-Inch/4.3mm Diameter, Amber: Amazon.com: Industrial & Scientific
3mm Wide-Angle GoPro Replacement Lens with S-Mount | CIL331
ELP CCTV Wide Angle 3mm 100 Degree No Distortion Lens Megapixel Lens with M12 lens Mount for all Usb Camera|no distortion|no distortion lenscctv wide angle lens - AliExpress
Explore Scientific 52° Series 3mm Waterproof Eyepiece