Canon EF600mm f/4L IS III USM Instructions Manual page 2

Thank you for purchasing a Canon product.
Canon's EF600mm f/4L IS III USM is an Image
Stabilizer-equipped super-telephoto lens for
use with EOS cameras.
"IS" stands for Image Stabilizer.
O O
"USM" stands for Ultrasonic Motor.
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Camera Firmware
Please use the latest version of firmware with
the camera in use. For details on whether the
firmware is the latest version or not, and for
details on updating the firmware, please check
the Canon website.
Conventions used in these instructions
Warning to prevent lens or camera malfunction
or damage.
Supplementary notes on using the lens and
taking pictures.
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