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Don Zeck Lens Cap for Canon 400mm f/2.8 USM IS or Canon 800mm f/5.6 USM IS Lenses
Finally a practical and effective lens cap to protect your front element from scratches dust rain and other hazards
This improved design features a handle to facilitate mounting or removing the lens cap while the lens hood is in the shooting position
The cap can be mounted on the lens while the hood is in the shooting position orin the stored position
The handle allows a firm grip on the cap so that it can be easily installed
The handle will compress for easy storage while your lens is in its case