Functions: T-mount lens for AI mount: T-mount lens with adapter ring, T/T2 lens replacement for Nikon cameras with AI mount D50 D90 D5100 D7000 D3 D5100 D3100 D3000 D60. Functional structure: The lens consists of 4 elements in 2 groups, with a lock used to attach the lens for precise shooting. The body is made entirely of metal, which provides a strong and durable construction. Ultra Multi Coating: Multi-layer coating technology reduces glare and sprite effect, ensuring vibrant colors and clear images. High-quality optical glass lenses guarantee high light transmission. Universal 1/4 inch mount: The 1/4 inch thread base along the lens allows for wide use on tripods and monopods. The base with ring can be rotated, convenient installation in seconds. Technical data: Material: metal Mount: T2 mount Adapter Ring Mount: T2-AI Replacement for: Nikon AI-mount D50 D90 D5100 D7000 D3 D5100 D5200 D3100 D3000 D60 Focal length: 420-800 mm zoom lens Aperture: f/8,3 @ 420 mm-f/16 @ 800 mm Optical structures: 4 elements in 2 groups Zoom system: linear push-pull Exposure: Automatic exposure is available in aperture preselection mode only on cameras with TTL measurement system; for the second camera, set the full instruction manual. Focusing: manual screw action (rotating) (not AF compliant) Minimum focusing distance: 1,6 meters (5,25 feet) from the front lens Filter size: 62 mm Diameter: 69mm Length: 24-35 cm / 9,45-13,38 inches (with caps) Lens dimensions: 24 * 7 * 7 cm / 9,45 * 2,76 * 2,76 inch Adapter ring dimensions: 6*6*1,3 cm/2,36*2,36*0,51 inch Weight: 659g / 18,3 oz Package Weight: 859g / 30,3oz List of things to pack: 1 * T2-AI adapter ring 1 * front cap 1 * rear cap 1 * Carrying Case