Canon EF 400 mm DO IS USM, 17/13
Canon EF 400 mm DO IS USM. Lens structure (elements/groups): 17/13, Lens viewing angle, diagonal: 6°, Thread diameter: 5.04" (12.8 cm). Filter size: 2.05" (52 mm), Weight: 4.28 lbs (1.94 kg). Magnification: 0.12x