This ultra-telephoto is incredibly compact and lightweight. Using an advanced reflex design, Samyang has created a mirror lens that is ideally suited for wildlife and sports photography. It has a fixed aperture of f8. It comes complete with a soft pouch and three (3) rear mounted, 30.5mm filters, (ND-2X, ND-4X & Skylight). Simple T-mount adapters screw on the lens to fit almost any camera.