Canon EOS-1D X Instruction Manual page 412

Use of genuine Canon accessories is recommended
This product is designed to achieve excellent performance when used with
genuine Canon accessories. Canon shall not be liable for any damage to this
product and/or accidents such as fire, etc., caused by the malfunction of non-
genuine Canon accessories (e.g., a leakage and/or explosion of a battery
pack). Please note that this warranty does not apply to repairs arising out of the
malfunction of non-genuine Canon accessories, although you may request
such repairs on a chargeable basis.
Battery Pack LP-E4N is designed for Canon products only. Using it with an
incompatible battery charger or product may result in malfunction or
accidents for which Canon cannot be held liable.
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