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From Youtube Software:
"Youtube Download button" will add virtual "Download button" to every page of Youtube (below the videos). You can download Youtube videos just one click using this button. Download video quality is very high, and it takes less time to comparing other downloaders because this software download video as MP4 format. You can use downloaded video of your mobiles or i-pods without converting. Download Button 100% just like part of Youtube.
When you click Download button it will start Download video. This software is small size and easy to download install and use. Software support most of the platforms and devices. Download it NOW Totally FREE.