Pentax SMC 400mm f/2.8 ED IF is manual focus ultra telephoto lens with automatic aperture. Ideal for advanced sports, action, and wildlife photographers. Its f/2.8 aperture allows for shooting in low light conditions. The internal focusing technology makes focusing smoother and faster. Extra-low dispersion elements produces high-resolution, high-contrast images. It features a built-in hood and tripod collar. FEATURES INCLUDE: Minimum Aperture: 32 Lens Construction: 8 groups 8 elements Angle of View: 6.2ø Diaphragm: Fully automatic Minimum Focusing Distance: 4.0m (13.1 ft.) Filter Size: 49mm (rear) Lens Hood: Built-in Lens Case: Trunk Case