Hi Madson,
These symbols describe rotational movement when the arm remains stationary and the forearm rotates over and forward.
These two examples represent  the same movement.
Sometimes, visually, one is a clearer representation of that movement that the other.

Date: Mon, 12 Mar 2012 07:47:38 -0500
From: [log in to unmask]
Subject: Re: Difference between symbols
To: [log in to unmask]

On 3/12/12 7:34 AM, Madson Barreto wrote:
[log in to unmask]"> Difference between symbols

Hello everyone!

What is different between these two arrows?

Have a good week!

Madson Barreto

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