Canon ST-E3-RT-V2 Manual page 69

Cautions:
Do not fire the flash near the eyes.

It may hurt the eyes.
Flash emits high temperatures when fired. Keep fingers, any other part of your body,

and objects away from the flash unit while taking pictures.
This may cause burns or malfunction of the flash.
Do not leave the product in places exposed to extremely high or low temperatures.

The product may become extremely hot/cold and cause burns or injury when touched.
Do not touch any parts inside the product.

This may cause injury.
Follow the cautions below. Otherwise physical injury
or property damage may result.
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