Canon EOC-1DX Instruction Manual page 397

Specifications
All the data above is based on Canon's testing standards and CIPA (Camera &
Imaging Products Association) testing standards and guidelines.
Dimensions, maximum diameter, length and weight listed above are based on
CIPA Guidelines (except weight for camera body only).
Product specifications and the exterior are subject to change without notice.
If a problem occurs with a non-Canon lens attached to the camera, consult the
respective lens maker.
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