Canon RF 400mm f/2.8 L IS USM Instructions Manual page 2

Thank you for purchasing a Canon product.
Canon RF400mm F2.8 L IS USM and
RF600mm F4 L IS USM are super-telephoto
lenses for use with EOS R series cameras.
"IS" stands for Image Stabilizer.
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"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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