Echo SRM-510ES Operator's Manual page 37

Trimming operation
When you turn off the engine, check to ensure that the trimmer
blade has stopped rotating before you lower the product to the
ground. Even if the engine has been turned off, the blade can
still cause an injury while free-wheeling.
The silencer will remain hot for some time after the engine has
been turned off. Carry the product with the silencer away from
you to avoid touching it with your body.
When carrying the product, always turn the engine off and fit
the trimmer blade cover over the trimmer blade.
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