Canon EOS 6D Basic Instruction Manual page 138

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-E6/LP-E6N is dedicated to 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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