From Canon 

We have confirmed that there are counterfeit Speedlite 600EX-RT flash products in circulation in the market. It has been reported that these products are being sold through various online marketplace websites. These counterfeit products have not been designed or manufactured by Canon, but fraudulently display the Canon logo, and may also fraudulently display other Canon and third party trademarks. Furthermore, these counterfeit products have not been manufactured or tested under the safety standards established by Canon, so we are unable to make representations concerning their safe operation, and there is a possibility that using one of these counterfeit products may cause adverse affects such as generation of fire and/or smoke.

The safety of our consumers is our utmost concern. Unlike genuine Canon products, counterfeit products may not meet government and industry safety standards. To ensure that you’re buying genuine Canon products, we recommend purchasing from a Canon Authorized Dealer or directly from Canon. Please be advised that Canon is not responsible for any malfunction, accident, or damage related to the use of any counterfeit product.

It has also been confirmed that the radio transmission wireless shooting function incorporated into genuine Canon Speedlite 600EX-RT flashes is not incorporated into the counterfeit product. This missing feature will limit the performance of the counterfeit flash, as compared with a genuine Canon Speedlite 600EX-RT flash.

We truly appreciate your attention to this matter and thank you for being a valued Canon customer.

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