Canon EF 400mm f2.8L IS II USM - Manual (Page 6)

ENG-5
1. Mounting and Detaching the Lens
See your camera’s instructions for details on
mounting and detaching the lens.
The lens mount has a rubber ring for enhanced
dust- and water-resistance. The rubber ring may
cause slight abrasions around the camera’s lens
mount, but this will not cause any problems. If the
rubber ring becomes worn, it is replaceable by a
Canon Service Center at cost.
Attaching the strap
Thread the end of the strap through the strap
mount on the lens and then back through the
clasp on the strap. Pull the strap tight and check
that there is no slack in the clasp.
After detaching the lens, place the lens with O O
the rear end up to prevent the lens surface and
contacts from getting scratched.
If the contacts get soiled, scratched, or have
O O
fingerprints on them, corrosion or faulty
connections can result. The camera and lens
may not operate properly.
If the contacts get soiled or have fingerprints on
O O
them, clean them with a soft cloth.
If you remove the lens, cover it with the dust cap.
O O
To attach it properly, align the lens mount index
and the  index of the dust cap as shown in
the diagram, and turn clockwise. To remove it,
reverse the order.
COP
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