Rokinon RK12M-E-SIL is an ultra-wide-angle lens tailored for APS-C-sized image sensors. It features a fixed focal length of 12mm. The lens has a bright f/2.0 aperture and a 9-blade diaphragm for smooth bokeh. The optical construction consists of 12 elements in 10 groups, including two aspherical lenses to minimize distortion and aberrations. The lens has a filter thread of 67mm and a maximum diameter of 72.5mm. It's designed for manual focus operation, allowing for precise control over the focus point. The lens is compatible with Sony E-mount cameras.