Orientation Locking Knob; Tripod Mount - Canon EF300mm f/2.8L IS II USM Instructions Manual

13. Using the Tripod
Mount
A tripod or monopod attaches to the tripod
mount on the lens.
Adjusting the Tripod Mount
By loosening the orientation locking knob on the
tripod mount you can rotate the camera to set
the image for any vertical or horizontal position.
Replacing the Tripod Mount
f/2.8L IS II USM only)
Replacement with the included monopod mount
can be done at a Canon Service Center at cost.
Since the mount requires special fastening, as
a safety precaution, do not replace the mount
yourself.
14. Security Slot
An attachment slot is provided for a wire-type
(EF400mm
security lock. The slot is located under the cover
for the orientation locking knob.
A wire-type security lock can be purchased
separately.
ENG-17