Canon 400mm lens f2.8 features

Focal length and maximum aperture: 400mm 1:2.8
Lens Construction (elements/groups): 17/13
Diagonal Angle of View: 6°10'
Focus adjustment: Inner focusing system with USM
Closest Focusing Distance (m): 3
Filter Diameter (mm): 52 Rear Drop-in

The Canon 400mm f2.8 includes:
E180C Front Lens Cap, Rear Lens Cap E, ET-155 Lens Hood, Lens Carrying Case 400, Wide Neck Strap, and 52mm Drop-In Gel Filter Holder.