The Edmund Optics HP Fixed Focal Length lens 86-574 is a 50mm focal length, 20 megapixel, C-mount lens with a M37.5 x 0.50 (Female) filter size, and less than -1.0% distortion. Edmund Optics HP fixed focal length C-mount lenses 6.5mm, 8mm, 12mm, 16mm, 25mm, and 35mm lenses are compatible with 1" and 1.1" sensor formats, while the 50mm lens is compatible with up to 4/3" sensor formats. These high performance, high quality machine vision lenses are built with a rugged design to withstand harsh industrial environments.