1、Important Parameters: C mount lens, 1in image size, 25mm focal length, 10mp pixel lens, relative aperture(D/fˊ) 1:1.4. 2、Good Image Quality: Optical coating makes your lens clearer and less prone to distortion, you need to be careful in use to avoid scratches. 3、Manual Iris Lens: C mount lens with manual focus and adjustable aperture, no lens shadow, no vignetting, high image quality. 4、Long Durability: The lens shell is made of high quality aluminum alloy, which is resistant to high temperature and durable. 5、Wide Application: C mount lens is widely used in home surveillance cameras, CCTV, TV cameras, video camera, DIY lenses, etc. Item Type: C Mount Lens Material: Aluminum alloy Focal Length: Approx. 25mm/0.98in Format: 1in (Diameter 16mm/0.63in, 12.8x9.6) Relative Aperture (D/fˊ): 1: 1.4 Mount: C Mounts Field Angle: 1in, 28.9°x21.8° 2/3in, 20.1°x15.2° 1/1.8in, 16.5°x12.4° 1/2in, 14.5°x10.5° Flange Back Focal Length: Approx. 17.53mm/0.69in Aperture (Iris): Manual/Lock (W/Lock) Distortion: 0.25% Resolution: 10MP Close Up Distance: Approx. 0.25m/0.82ft Dimension: Approx. 40.0x56mm/1.58x2.2inFilter Size: M37.5x0.5p Application: Surveillance camera replacement lens, DIY lens 1 x C Mount Lens 1 x Adapter